Lightweight mounting of a secondary copy of file system data

ABSTRACT

A data storage system allows a user to search a secondary copy such as a back up, archive, or snapshot and receive an abbreviated version of the secondary copy of the file system as a result of the search. The abbreviated version of the secondary copy of the file system may include metadata such as a listing of secondary copy data that correspond with a search term or other filtering criteria provided by the user. An operating system of the user&#39;s computing device may mount the abbreviated version so that it can be displayed within a view of the file system of the computing device. Once a user selects one or more desired data objects listed in the abbreviated version, the selected actual one or more data objects are retrieved from secondary storage.

CROSS-REFERENCE TO RELATED APPLICATION

Any and all applications for which a foreign or domestic priority claimis identified in the Application Data Sheet as filed with the presentapplication are hereby incorporated by reference under 37 CFR 1.57.

BACKGROUND

Businesses worldwide recognize the commercial value of their data andseek reliable, cost-effective ways to protect the information stored ontheir computer networks while minimizing impact on productivity.Protecting information is often part of a routine process that isperformed within an organization.

A company might back up critical computing systems such as databases,file servers, web servers, and so on as part of a daily, weekly, ormonthly maintenance schedule. The company may similarly protectcomputing systems used by each of its employees, such as those used byan accounting department, marketing department, engineering department,and so forth.

Given the rapidly expanding volume of data under management, companiesalso continue to seek innovative techniques for managing data growth, inaddition to protecting data. For instance, companies often implementmigration techniques for moving data to lower cost storage over time anddata reduction techniques for reducing redundant data, pruning lowerpriority data, etc.

Enterprises also increasingly view their stored data as a valuableasset. Along these lines, customers are looking for solutions that notonly protect and manage, but also leverage their data. For instance,solutions providing data analysis capabilities, improved datapresentation and access features, and the like, are in increasingdemand.

As computers have become an integral part of business operations, manyenterprises have come to rely on computer networks to store and backuptheir information. In addition, enterprises have come to rely on theability to restore information quickly and efficiently when needed. Inaddition, enterprises are storing and backing up ever increasing amountsof data. Ensuring that the data can be searched and easily restored hasbecome increasingly complex as the methods for storing and backing updata have become more sophisticated and the amount of data has increasedsignificantly.

The increased amount of data that is backed up and stored places heavydemands on system resources. Because accessing data in secondary storagecan be relatively slow and resource intensive, these demands can beespecially burdensome when a user attempts to search through or restoresecondary copies of production data. Likewise, users may spendsignificant amounts of time trying to find and retrieve the desireddata.

SUMMARY

Systems and methods are described that allow a user to search through asecondary copy of data (e.g., a back up, archive, or snapshot copy of afile system) without first retrieving all of the secondary copy data.Instead, the system implements lightweight mounting of at least aportion of the secondary copy of the file system data. The mounting canalso be selective, based on user-defined filtering criteria, furtherimproving performance and improving usability. For example, the userreceives an abbreviated file system as a result of a user-defined searchor other filtering criteria. The abbreviated file system may include alisting of data objects in the secondary copy (e.g., files, directories,etc.) that satisfy or otherwise correspond with filtering criteria suchas a search term provided by the user. An operating system of the user'scomputing device may mount the abbreviated file system so that it can beviewed within a file system of the computing device. Once the userselects a desired data object(s) listed in the abbreviated file system,the selected data may be retrieved from a secondary storage medium. Inthis manner, the system provides a user-definable filtered view of thesecondary copy of the file system, without unnecessarily retrieving dataobjects from secondary storage, improving performance.

One aspect of the disclosure provides a networked data storage system.The networked data storage system includes a user computing deviceconfigured to transmit filtering criteria (e.g., a search term) to amedia agent that is in communication with secondary storage, where thesecondary storage maintains a secondary copy of at least a portion of afile system. The user computing device may be further configured toreceive an abbreviated version of the secondary copy of the file systemfrom the media agent. The abbreviated version of the secondary copy ofthe file system may comprise a listing of data objects in the secondarycopy that are identified by the media agent as satisfying the filteringcriteria. The user computing device may be further configured to mountthe abbreviated version of the secondary copy of the file system. Themounted abbreviated version of the secondary copy of the file system maybe displayed within a view of a file system of the user computingdevice.

Another aspect of the disclosure provides a method for searching a filesystem. The method includes transmitting, by a user computing device,filtering criteria to a media agent that is in communication withsecondary storage, where the secondary storage maintains a secondarycopy of at least a portion of a file system. The method further includesreceiving metadata corresponding to an abbreviated version of thesecondary copy of the file system from the media agent. The abbreviatedversion of the secondary copy of the file system may comprise a listingof data objects existing in a secondary copy of production data that isstored in secondary storage, and that are identified by the media agentas satisfying the filtering criteria. The method further includesmounting the abbreviated version of the secondary copy of the filesystem. The mounted abbreviated version of the secondary copy of thefile system may be displayed within a view of a file system of the usercomputing device.

Another aspect of the disclosure provides a networked data storagesystem. The networked data storage system includes a storage managerconfigured to cause a graphical user interface to be presented on adisplay, where the graphical user interface includes a filter field. Thenetworked data storage system further includes secondary storageconfigured to maintain a secondary copy of at least a portion of a filesystem. The networked data storage system further includes a mediaagent, in communication with the secondary storage, including a contentindexing module executing on a first computing device and configured, inresponse to instructions from the storage manager, to receive filteringcriteria entered into the filter field. The media agent is furtherconfigured to identify data objects in the secondary copy that satisfythe filtering criteria. The media agent is further configured togenerate an abbreviated version of the secondary copy of the file systembased on the identified data objects. The abbreviated version of thesecondary copy of the file system may include a listing of data objectsin the secondary copy that are identified by the media agent assatisfying the filtering criteria. The media agent is further configuredto transmit the abbreviated version of the secondary copy of the filesystem to a second computing device. The second computing device may beconfigured to mount the abbreviated version of the secondary copy of thefile system.

Another aspect of the disclosure provides a method for creating anabbreviated file system. The method includes causing, by a storagemanager, a graphical user interface to be presented on a display, wherethe graphical user interface may include a filter field. The methodfurther includes maintaining, by a secondary storage, a secondary copyof at least a portion of a file system. The method further includes, inresponse to instructions from the storage manager, receiving filteringcriteria entered into the filter field. The method further includesidentifying data objects in the secondary copy that satisfy thefiltering criteria. The method further includes generating anabbreviated version of the secondary copy of the file system based onthe identified data objects. The abbreviated version of the secondarycopy of the file system may include a listing of data objects in thesecondary copy that are identifies as satisfying the filtering criteria.The method further includes transmitting the abbreviated version of thesecondary copy of the file system to a second computing device. Thesecond computing device may be configured to mount the abbreviatedversion of the secondary copy of the file system.

BRIEF DESCRIPTION OF THE DRAWINGS

Throughout the drawings, reference numbers are re-used to indicatecorrespondence between referenced elements. The drawings are provided toillustrate embodiments of the inventive subject matter described hereinand not to limit the scope thereof.

FIG. 1A is a block diagram illustrating an exemplary informationmanagement system.

FIG. 1B is a detailed view of a primary storage device, a secondarystorage device, and some examples of primary data and secondary copydata.

FIG. 1C is a block diagram of an exemplary information management systemincluding a storage manager, one or more data agents, and one or moremedia agents.

FIG. 1D is a block diagram illustrating a scalable informationmanagement system.

FIG. 1E illustrates certain secondary copy operations according to anexemplary storage policy.

FIG. 2 is a block diagram illustrating an example data storageenvironment in which aspects of the inventive systems and methods mayoperate.

FIG. 3A depicts an illustrative user interface that enables a user tosearch through secondary copies of production data, such as backups,archives, and/or snapshots.

FIG. 3B depicts an illustrative user interface that enables a user tobrowse through an abbreviated file system.

FIG. 4 shows a flow diagram illustrative of embodiments of a routineimplemented by a media agent for generating an abbreviated file system.

FIG. 5 shows a flow diagram illustrative of embodiments of a routineimplemented by a computing device for mounting an abbreviated filesystem and retrieving a copy of a data object from secondary storage.

DETAILED DESCRIPTION

Systems and methods are described herein for implementing lightweightmounting of a secondary copy in a data storage system. Examples of suchsystems and methods are discussed in further detail herein, e.g., withrespect to FIGS. 2-5. Mounting of a secondary copy may additionally beimplemented by information management systems such as those that willnow be described with respect to FIGS. 1A-1E. And, as will be described,the componentry for implementing the secondary copy mounting techniquesdescribed herein can be incorporated into and implemented by suchsystems.

Information Management System Overview

With the increasing importance of protecting and leveraging data,organizations simply cannot afford to take the risk of losing criticaldata. Moreover, runaway data growth and other modern realities makeprotecting and managing data an increasingly difficult task. There istherefore a need for efficient, powerful, and user-friendly solutionsfor protecting and managing data. Depending on the size of theorganization, there are typically many data production sources which areunder the purview of tens, hundreds, or even thousands of employees orother individuals. In the past, individual employees were sometimesresponsible for managing and protecting their data. A patchwork ofhardware and software point solutions have been applied in other cases.These solutions were often provided by different vendors and had limitedor no interoperability.

Certain embodiments described herein provide systems and methods capableof addressing these and other shortcomings of prior approaches byimplementing unified, organization-wide information management. FIG. 1Ashows one such information management system 100, which generallyincludes combinations of hardware and software configured to protect andmanage data and metadata generated and used by the various computingdevices in the information management system 100.

The organization which employs the information management system 100 maybe a corporation or other business entity, non-profit organization,educational institution, household, governmental agency, or the like.

Generally, the systems and associated components described herein may becompatible with and/or provide some or all of the functionality of thesystems and corresponding components described in one or more of thefollowing U.S. patents and patent application publications assigned toCommVault Systems, Inc., each of which is hereby incorporated in itsentirety by reference herein:

U.S. Pat. Pub. No. 2010-0332456, entitled “DATA OBJECT STORE AND SERVERFOR A CLOUD STORAGE ENVIRONMENT, INCLUDING DATA DEDUPLICATION AND DATAMANAGEMENT ACROSS MULTIPLE CLOUD STORAGE SITES”;

U.S. Pat. No. 7,035,880, entitled “MODULAR BACKUP AND RETRIEVAL SYSTEMUSED IN CONJUNCTION WITH A STORAGE AREA NETWORK”;

U.S. Pat. No. 7,343,453, entitled “HIERARCHICAL SYSTEMS AND METHODS FORPROVIDING A UNIFIED VIEW OF STORAGE INFORMATION”;

U.S. Pat. No. 7,395,282, entitled “HIERARCHICAL BACKUP AND RETRIEVALSYSTEM”;

U.S. Pat. No. 7,246,207, entitled “SYSTEM AND METHOD FOR DYNAMICALLYPERFORMING STORAGE OPERATIONS IN A COMPUTER NETWORK”;

U.S. Pat. No. 7,747,579, entitled “METABASE FOR FACILITATING DATACLASSIFICATION”;

U.S. Pat. No. 8,229,954, entitled “MANAGING COPIES OF DATA”;

U.S. Pat. No. 7,617,262, entitled “SYSTEM AND METHODS FOR MONITORINGAPPLICATION DATA IN A DATA REPLICATION SYSTEM”;

U.S. Pat. No. 7,529,782, entitled “SYSTEM AND METHODS FOR PERFORMING ASNAPSHOT AND FOR RESTORING DATA”;

U.S. Pat. No. 8,230,195, entitled “SYSTEM AND METHOD FOR PERFORMINGAUXILIARY STORAGE OPERATIONS”;

U.S. Pat. No. 8,364,652, entitled “CONTENT-ALIGNED, BLOCK-BASEDDEDUPLICATION”;

U.S. Pat. Pub. No. 2006/0224846, entitled “SYSTEM AND METHOD TO SUPPORTSINGLE INSTANCE STORAGE OPERATIONS”;

U.S. Pat. Pub. No. 2009/0329534, entitled “APPLICATION-AWARE AND REMOTESINGLE INSTANCE DATA MANAGEMENT”;

U.S. Pat. Pub. No. 2012/0150826, entitled “DISTRIBUTED DEDUPLICATEDSTORAGE SYSTEM”;

U.S. Pat. Pub. No. 2012/0150818, entitled “CLIENT-SIDE REPOSITORY IN ANETWORKED DEDUPLICATED STORAGE SYSTEM”;

U.S. Pat. No. 8,170,995, entitled “METHOD AND SYSTEM FOR OFFLINEINDEXING OF CONTENT AND CLASSIFYING STORED DATA”; and

U.S. Pat. No. 8,156,086, entitled “SYSTEMS AND METHODS FOR STORED DATAVERIFICATION”.

The illustrated information management system 100 includes one or moreclient computing device 102 having at least one application 110executing thereon, and one or more primary storage devices 104 storingprimary data 112. The client computing device(s) 102 and the primarystorage devices 104 may generally be referred to in some cases as aprimary storage subsystem 117.

Depending on the context, the term “information management system” canrefer to generally all of the illustrated hardware and softwarecomponents. Or, in other instances, the term may refer to only a subsetof the illustrated components.

For instance, in some cases information management system 100 generallyrefers to a combination of specialized components used to protect, move,manage, manipulate and/or process data and metadata generated by theclient computing devices 102. However, the term may generally not referto the underlying components that generate and/or store the primary data112, such as the client computing devices 102 themselves, theapplications 110 and operating system residing on the client computingdevices 102, and the primary storage devices 104.

As an example, “information management system” may sometimes refer onlyto one or more of the following components and corresponding datastructures: storage managers, data agents, and media agents. Thesecomponents will be described in further detail below.

Client Computing Devices

There are typically a variety of sources in an organization that producedata to be protected and managed. As just one illustrative example, in acorporate environment such data sources can be employee workstations andcompany servers such as a mail server, a web server, or the like. In theinformation management system 100, the data generation sources includethe one or more client computing devices 102.

The client computing devices 102 may include, without limitation, one ormore: workstations, personal computers, desktop computers, or othertypes of generally fixed computing systems such as mainframe computersand minicomputers.

The client computing devices 102 can also include mobile or portablecomputing devices, such as one or more laptops, tablet computers,personal data assistants, mobile phones (such as smartphones), and othermobile or portable computing devices such as embedded computers, set topboxes, vehicle-mounted devices, wearable computers, etc.

In some cases, each client computing device 102 is associated with oneor more users and/or corresponding user accounts, of employees or otherindividuals.

The term “client computing device” is used herein because theinformation management system 100 generally “serves” the data managementand protection needs for the data generated by the client computingdevices 102. However, the use of this term does not imply that theclient computing devices 102 cannot be “servers” in other respects. Forinstance, a particular client computing device 102 may act as a serverwith respect to other devices, such as other client computing devices102. As just a few examples, the client computing devices 102 caninclude mail servers, file servers, database servers, and web servers.

The client computing devices 102 may additionally include virtualizedand/or cloud computing resources. For instance, one or more virtualmachines may be provided to the organization by a third-party cloudservice vendor. Or, in some embodiments, the client computing devices102 include one or more virtual machine(s) running on a virtual machinehost computing device operated by the organization. As one example, theorganization may use one virtual machine as a database server andanother virtual machine as a mail server. A virtual machine manager(VMM) (e.g., a Hypervisor) may manage the virtual machines, and resideand execute on the virtual machine host computing device.

Each client computing device 102 may have one or more applications 110(e.g., software applications) executing thereon which generate andmanipulate the data that is to be protected from loss.

The applications 110 generally facilitate the operations of anorganization (or multiple affiliated organizations), and can include,without limitation, mail server applications (e.g., Microsoft ExchangeServer), file server applications, mail client applications (e.g.,Microsoft Exchange Client), database applications (e.g., SQL, Oracle,SAP, Lotus Notes Database), word processing applications (e.g.,Microsoft Word), spreadsheet applications, financial applications,presentation applications, browser applications, mobile applications,entertainment applications, and so on.

The applications 110 can include at least one operating system (e.g.,Microsoft Windows, Mac OS X, iOS, IBM z/OS, Linux, other Unix-basedoperating systems, etc.), which may support one or more file systems andhost the other applications 110.

As shown, the client computing devices 102 and other components in theinformation management system 100 can be connected to one another viaone or more communication pathways 114. The communication pathways 114can include one or more networks or other connection types including asany of following, without limitation: the Internet, a wide area network(WAN), a local area network (LAN), a Storage Area Network (SAN), a FibreChannel connection, a Small Computer System Interface (SCSI) connection,a virtual private network (VPN), a token ring or TCP/IP based network,an intranet network, a point-to-point link, a cellular network, awireless data transmission system, a two-way cable system, aninteractive kiosk network, a satellite network, a broadband network, abaseband network, other appropriate wired, wireless, or partiallywired/wireless computer or telecommunications networks, combinations ofthe same or the like. The communication pathways 114 in some cases mayalso include application programming interfaces (APIs) including, e.g.,cloud service provider APIs, virtual machine management APIs, and hostedservice provider APIs.

Primary Data and Exemplary Primary Storage Devices

Primary data 112 according to some embodiments is production data orother “live” data generated by the operating system and otherapplications 110 residing on a client computing device 102. The primarydata 112 is stored on the primary storage device(s) 104 and is organizedvia a file system supported by the client computing device 102. Forinstance, the client computing device(s) 102 and correspondingapplications 110 may create, access, modify, write, delete, andotherwise use primary data 112.

Primary data 112 is generally in the native format of the sourceapplication 110. According to certain aspects, primary data 112 is aninitial or first (e.g., created before any other copies or before atleast one other copy) stored copy of data generated by the sourceapplication 110. Primary data 112 in some cases is created substantiallydirectly from data generated by the corresponding source applications110.

The primary data 112 may sometimes be referred to as a “primary copy” inthe sense that it is a discrete set of data. However, the use of thisterm does not necessarily imply that the “primary copy” is a copy in thesense that it was copied or otherwise derived from another storedversion.

The primary storage devices 104 storing the primary data 112 may berelatively fast and/or expensive (e.g., a disk drive, a hard-disk array,solid state memory, etc.). In addition, primary data 112 may be intendedfor relatively short term retention (e.g., several hours, days, orweeks).

According to some embodiments, the client computing device 102 canaccess primary data 112 from the primary storage device 104 by makingconventional file system calls via the operating system. Primary data112 representing files may include structured data (e.g., databasefiles), unstructured data (e.g., documents), and/or semi-structureddata. Some specific examples are described below with respect to FIG.1B.

It can be useful in performing certain tasks to break the primary data112 up into units of different granularities. In general, primary data112 can include files, directories, file system volumes, data blocks,extents, or any other types or granularities of data objects. As usedherein, a “data object” can refer to both (1) any file that is currentlyaddressable by a file system or that was previously addressable by thefile system (e.g., an archive file) and (2) a subset of such a file.

As will be described in further detail, it can also be useful inperforming certain functions of the information management system 100 toaccess and modify metadata within the primary data 112. Metadatagenerally includes information about data objects or characteristicsassociated with the data objects.

Metadata can include, without limitation, one or more of the following:the data owner (e.g., the client or user that generates the data), thelast modified time (e.g., the time of the most recent modification ofthe data object), a data object name (e.g., a file name), a data objectsize (e.g., a number of bytes of data), information about the content(e.g., an indication as to the existence of a particular search term),to/from information for email (e.g., an email sender, recipient, etc.),creation date, file type (e.g., format or application type), lastaccessed time, application type (e.g., type of application thatgenerated the data object), location/network (e.g., a current, past orfuture location of the data object and network pathways to/from the dataobject), frequency of change (e.g., a period in which the data object ismodified), business unit (e.g., a group or department that generates,manages or is otherwise associated with the data object), and aginginformation (e.g., a schedule, such as a time period, in which the dataobject is migrated to secondary or long term storage), boot sectors,partition layouts, file location within a file folder directorystructure, user permissions, owners, groups, access control lists[ACLs]), system metadata (e.g., registry information), combinations ofthe same or the like.

In addition to metadata generated by or related to file systems andoperating systems, some of the applications 110 maintain indices ofmetadata for data objects, e.g., metadata associated with individualemail messages. Thus, each data object may be associated withcorresponding metadata. The use of metadata to perform classificationand other functions is described in greater detail below.

Each of the client computing devices 102 are associated with and/or incommunication with one or more of the primary storage devices 104storing corresponding primary data 112. A client computing device 102may be considered to be “associated with” or “in communication with” aprimary storage device 104 if it is capable of one or more of: storingdata to the primary storage device 104, retrieving data from the primarystorage device 104, and modifying data retrieved from a primary storagedevice 104.

The primary storage devices 104 can include, without limitation, diskdrives, hard-disk arrays, semiconductor memory (e.g., solid statedrives), and network attached storage (NAS) devices. In some cases, theprimary storage devices 104 form part of a distributed file system. Theprimary storage devices 104 may have relatively fast I/O times and/orare relatively expensive in comparison to the secondary storage devices108. For example, the information management system 100 may generallyregularly access data and metadata stored on primary storage devices104, whereas data and metadata stored on the secondary storage devices108 is accessed relatively less frequently.

In some cases, each primary storage device 104 is dedicated to anassociated client computing devices 102. For instance, a primary storagedevice 104 in one embodiment is a local disk drive of a correspondingclient computing device 102. In other cases, one or more primary storagedevices 104 can be shared by multiple client computing devices 102. Asone example, a primary storage device 104 can be a disk array shared bya group of client computing devices 102, such as one of the followingtypes of disk arrays: EMC Clariion, EMC Symmetrix, EMC Celerra, DellEqualLogic, IBM XIV, NetApp FAS, HP EVA, and HP 3PAR.

The information management system 100 may also include hosted services(not shown), which may be hosted in some cases by an entity other thanthe organization that employs the other components of the informationmanagement system 100. For instance, the hosted services may be providedby various online service providers to the organization. Such serviceproviders can provide services including social networking services,hosted email services, or hosted productivity applications or otherhosted applications).

Hosted services may include software-as-a-service (SaaS),platform-as-a-service (PaaS), application service providers (ASPs),cloud services, or other mechanisms for delivering functionality via anetwork. As it provides services to users, each hosted service maygenerate additional data and metadata under management of theinformation management system 100, e.g., as primary data 112. In somecases, the hosted services may be accessed using one of the applications110. As an example, a hosted mail service may be accessed via browserrunning on a client computing device 102.

Secondary Copies and Exemplary Secondary Storage Devices

The primary data 112 stored on the primary storage devices 104 may becompromised in some cases, such as when an employee deliberately oraccidentally deletes or overwrites primary data 112 during their normalcourse of work. Or the primary storage devices 104 can be damaged orotherwise corrupted.

For recovery and/or regulatory compliance purposes, it is thereforeuseful to generate copies of the primary data 112. Accordingly, theinformation management system 100 includes one or more secondary storagecomputing devices 106 and one or more secondary storage devices 108configured to create and store one or more secondary copies 116 of theprimary data 112 and associated metadata. The secondary storagecomputing devices 106 and the secondary storage devices 108 may bereferred to in some cases as a secondary storage subsystem 118.

Creation of secondary copies 116 can help meet information managementgoals, such as: restoring data and/or metadata if an original version(e.g., of primary data 112) is lost (e.g., by deletion, corruption, ordisaster); allowing point-in-time recovery; complying with regulatorydata retention and electronic discovery (e-discovery) requirements;reducing utilized storage capacity; facilitating organization and searchof data; improving user access to data files across multiple computingdevices and/or hosted services; and implementing data retentionpolicies.

Types of secondary copy operations can include, without limitation,backup operations, archive operations, snapshot operations, replicationoperations (e.g., continuous data replication [CDR]), data retentionpolicies such as information lifecycle management and hierarchicalstorage management operations, and the like. These specific typesoperations are discussed in greater detail below.

Regardless of the type of secondary copy operation, the client computingdevices 102 access or receive primary data 112 and communicate the data,e.g., over the communication pathways 114, for storage in the secondarystorage device(s) 108.

A secondary copy 116 can comprise a separate stored copy of applicationdata that is derived from one or more earlier created, stored copies(e.g., derived from primary data 112 or another secondary copy 116).Secondary copies 116 can include point-in-time data, and may be intendedfor relatively long-term retention (e.g., weeks, months or years),before some or all of the data is moved to other storage or isdiscarded.

In some cases, a secondary copy 116 is a copy of application datacreated and stored subsequent to at least one other stored instance(e.g., subsequent to corresponding primary data 112 or to anothersecondary copy 116), in a different storage device than at least oneprevious stored copy, and/or remotely from at least one previous storedcopy. Secondary copies 116 may be stored in relatively slow and/or lowcost storage (e.g., magnetic tape). A secondary copy 116 may be storedin a backup or archive format, or in some other format different thanthe native source application format or other primary data format.

In some cases, secondary copies 116 are indexed so users can browse andrestore at another point in time. After creation of a secondary copy 116representative of certain primary data 112, a pointer or other locationindicia (e.g., a stub) may be placed in primary data 112, or beotherwise associated with primary data 112 to indicate the currentlocation on the secondary storage device(s) 108.

Since an instance a data object or metadata in primary data 112 maychange over time as it is modified by an application 110 (or hostedservice or the operating system), the information management system 100may create and manage multiple secondary copies 116 of a particular dataobject or metadata, each representing the state of the data object inprimary data 112 at a particular point in time. Moreover, since aninstance of a data object in primary data 112 may eventually be deletedfrom the primary storage device 104 and the file system, the informationmanagement system 100 may continue to manage point-in-timerepresentations of that data object, even though the instance in primarydata 112 no longer exists.

For virtualized computing devices the operating system and otherapplications 110 of the client computing device(s) 102 may executewithin or under the management of virtualization software (e.g., a VMM),and the primary storage device(s) 104 may comprise a virtual diskcreated on a physical storage device. The information management system100 may create secondary copies 116 of the files or other data objectsin a virtual disk file and/or secondary copies 116 of the entire virtualdisk file itself (e.g., of an entire .vmdk file).

Secondary copies 116 may be distinguished from corresponding primarydata 112 in a variety of ways, some of which will now be described.First, as discussed, secondary copies 116 can be stored in a differentformat (e.g., backup, archive, or other non-native format) than primarydata 112. For this or other reasons, secondary copies 116 may not bedirectly useable by the applications 110 of the client computing device102, e.g., via standard system calls or otherwise without modification,processing, or other intervention by the information management system100.

Secondary copies 116 are also often stored on a secondary storage device108 that is inaccessible to the applications 110 running on the clientcomputing devices 102 (and/or hosted services). Some secondary copies116 may be “offline copies,” in that they are not readily available(e.g. not mounted to tape or disk). Offline copies can include copies ofdata that the information management system 100 can access without humanintervention (e.g. tapes within an automated tape library, but not yetmounted in a drive), and copies that the information management system100 can access only with at least some human intervention (e.g. tapeslocated at an offsite storage site).

The secondary storage devices 108 can include any suitable type ofstorage device such as, without limitation, one or more tape libraries,disk drives or other magnetic, non-tape storage devices, optical mediastorage devices, solid state storage devices, NAS devices, combinationsof the same, and the like. In some cases, the secondary storage devices108 are provided in a cloud (e.g. a private cloud or one operated by athird-party vendor).

The secondary storage device(s) 108 in some cases comprises a disk arrayor a portion thereof. In some cases, a single storage device (e.g., adisk array) is used for storing both primary data 112 and at least somesecondary copies 116. In one example, a disk array capable of performinghardware snapshots stores primary data 112 and creates and storeshardware snapshots of the primary data 112 as secondary copies 116.

The Use of Intermediary Devices for Creating Secondary Copies

Creating secondary copies can be a challenging task. For instance, therecan be hundreds or thousands of client computing devices 102 continuallygenerating large volumes of primary data 112 to be protected. Also,there can be significant overhead involved in the creation of secondarycopies 116. Moreover, secondary storage devices 108 may be specialpurpose components, and interacting with them can require specializedintelligence.

In some cases, the client computing devices 102 interact directly withthe secondary storage device 108 to create the secondary copies 116.However, in view of the factors described above, this approach cannegatively impact the ability of the client computing devices 102 toserve the applications 110 and produce primary data 112. Further, theclient computing devices 102 may not be optimized for interaction withthe secondary storage devices 108.

Thus, in some embodiments, the information management system 100includes one or more software and/or hardware components which generallyact as intermediaries between the client computing devices 102 and thesecondary storage devices 108. In addition to off-loading certainresponsibilities from the client computing devices 102, theseintermediary components can provide other benefits. For instance, asdiscussed further below with respect to FIG. 1D, distributing some ofthe work involved in creating secondary copies 116 can enhancescalability.

The intermediary components can include one or more secondary storagecomputing devices 106 as shown in FIG. 1A and/or one or more mediaagents, which can be software modules residing on correspondingsecondary storage computing devices 106 (or other appropriate devices).Media agents are discussed below (e.g., with respect to FIGS. 1C-1E).

The secondary storage computing device(s) 106 can comprise anyappropriate type of computing device and can include, withoutlimitation, any of the types of fixed and portable computing devicesdescribed above with respect to the client computing devices 102. Insome cases, the secondary storage computing device(s) 106 includespecialized hardware and/or software componentry for interacting withthe secondary storage devices 108.

To create a secondary copy 116, the client computing device 102communicates the primary data 112 to be copied (or a processed versionthereof) to the designated secondary storage computing device 106, viathe communication pathway 114. The secondary storage computing device106 in turn conveys the received data (or a processed version thereof)to the secondary storage device 108. In some such configurations, thecommunication pathway 114 between the client computing device 102 andthe secondary storage computing device 106 comprises a portion of a LAN,WAN or SAN. In other cases, at least some client computing devices 102communicate directly with the secondary storage devices 108 (e.g., viaFibre Channel or SCSI connections).

Exemplary Primary Data and an Exemplary Secondary Copy

FIG. 1B is a detailed view showing some specific examples of primarydata stored on the primary storage device(s) 104 and secondary copy datastored on the secondary storage device(s) 108, with other components inthe system removed for the purposes of illustration. Stored on theprimary storage device(s) 104 are primary data objects including wordprocessing documents 119A-B, spreadsheets 120, presentation documents122, video files 124, image files 126, email mailboxes 128 (andcorresponding email messages 129A-C), html/xml or other types of markuplanguage files 130, databases 132 and corresponding tables 133A-133C).

Some or all primary data objects are associated with a primary copy ofobject metadata (e.g., “Meta1-11”), which may be file system metadataand/or application specific metadata. Stored on the secondary storagedevice(s) 108 are secondary copy objects 134A-C which may include copiesof or otherwise represent corresponding primary data objects andmetadata.

As shown, the secondary copy objects 134A-C can individually representmore than one primary data object. For example, secondary copy dataobject 134A represents three separate primary data objects 133C, 122 and129C (represented as 133C′, 122′ and 129C′, respectively). Moreover, asindicated by the prime mark (′), a secondary copy object may store arepresentation of a primary data object or metadata differently than theoriginal format, e.g., in a compressed, encrypted, deduplicated, orother modified format.

Exemplary Information Management System Architecture

The information management system 100 can incorporate a variety ofdifferent hardware and software components, which can in turn beorganized with respect to one another in many different configurations,depending on the embodiment. There are critical design choices involvedin specifying the functional responsibilities of the components and therole of each component in the information management system 100. Forinstance, as will be discussed, such design choices can impactperformance as well as the adaptability of the information managementsystem 100 to data growth or other changing circumstances.

FIG. 1C shows an information management system 100 designed according tothese considerations and which includes: a central storage orinformation manager 140 configured to perform certain control functions,one or more data agents 142 executing on the client computing device(s)102 configured to process primary data 112, and one or more media agents144 executing on the one or more secondary storage computing devices 106for performing tasks involving the secondary storage devices 108.

Storage Manager

As noted, the number of components in the information management system100 and the amount of data under management can be quite large. Managingthe components and data is therefore a significant task, and a task thatcan grow in an often unpredictable fashion as the quantity of componentsand data scale to meet the needs of the organization.

For these and other reasons, according to certain embodiments,responsibility for controlling the information management system 100, orat least a significant portion of that responsibility, is allocated tothe storage manager 140.

By distributing control functionality in this manner, the storagemanager 140 can be adapted independently according to changingcircumstances. Moreover, a host computing device can be selected to bestsuit the functions of the storage manager 140. These and otheradvantages are described in further detail below with respect to FIG.1D.

The storage manager 140 may be a software module or other application.The storage manager generally initiates, coordinates and/or controlsstorage and other information management operations performed by theinformation management system 100, e.g., to protect and control theprimary data 112 and secondary copies 116 of data and metadata.

As shown by the dashed, arrowed lines, the storage manager 140 maycommunicate with and/or control some or all elements of the informationmanagement system 100, such as the data agents 142 and media agents 144.Thus, in certain embodiments, control information originates from thestorage manager 140, whereas payload data and metadata is generallycommunicated between the data agents 142 and the media agents 144 (orotherwise between the client computing device(s) 102 and the secondarystorage computing device(s) 106), e.g., at the direction of the storagemanager 140. In other embodiments, some information managementoperations are controlled by other components in the informationmanagement system 100 (e.g., the media agent(s) 144 or data agent(s)142), instead of or in combination with the storage manager 140.

According to certain embodiments, the storage manager provides one ormore of the following functions:

-   -   initiating execution of secondary copy operations;    -   managing secondary storage devices 108 and inventory/capacity of        the same;    -   allocating secondary storage devices 108 for secondary storage        operations;    -   monitoring completion of and providing status reporting related        to secondary storage operations;    -   tracking age information relating to secondary copies 116,        secondary storage devices 108, and comparing the age information        against retention guidelines;    -   tracking movement of data within the information management        system 100;    -   tracking logical associations between components in the        information management system 100;    -   protecting metadata associated with the information management        system 100; and    -   implementing operations management functionality.

The storage manager 140 may maintain a database 146 ofmanagement-related data and information management policies 148. Thedatabase 146 may include a management index 150 or other data structurethat stores logical associations between components of the system, userpreferences and/or profiles (e.g., preferences regarding encryption,compression, or deduplication of primary or secondary copy data,preferences regarding the scheduling, type, or other aspects of primaryor secondary copy or other operations, mappings of particularinformation management users or user accounts to certain computingdevices or other components, etc.), management tasks, mediacontainerization, or other useful data. For example, the storage manager140 may use the index 150 to track logical associations between mediaagents 144 and secondary storage devices 108 and/or movement of datafrom primary storage devices 104 to secondary storage devices 108.

Administrators and other employees may be able to manually configure andinitiate certain information management operations on an individualbasis. But while this may be acceptable for some recovery operations orother relatively less frequent tasks, it is often not workable forimplementing on-going organization-wide data protection and management.

Thus, the information management system 100 may utilize informationmanagement policies 148 for specifying and executing informationmanagement operations (e.g., on an automated basis). Generally, aninformation management policy 148 can include a data structure or otherinformation source that specifies a set of parameters (e.g., criteriaand rules) associated with storage or other information managementoperations.

The storage manager database 146 may maintain the information managementpolicies 148 and associated data, although the information managementpolicies 148 can be stored in any appropriate location. For instance, astorage policy may be stored as metadata in a media agent database 152or in a secondary storage device 108 (e.g., as an archive copy) for usein restore operations or other information management operations,depending on the embodiment. Information management policies 148 aredescribed further below.

According to certain embodiments, the storage manager database 146comprises a relational database (e.g., an SQL database) for trackingmetadata, such as metadata associated with secondary copy operations(e.g., what client computing devices 102 and corresponding data wereprotected). This and other metadata may additionally be stored in otherlocations, such as at the secondary storage computing devices 106 or onthe secondary storage devices 108, allowing data recovery without theuse of the storage manager 140.

As shown, the storage manager 140 may include a jobs agent 156, a userinterface 158, and a management agent 154, all of which may beimplemented as interconnected software modules or application programs.

The jobs agent 156 in some embodiments initiates, controls, and/ormonitors the status of some or all storage or other informationmanagement operations previously performed, currently being performed,or scheduled to be performed by the information management system 100.For instance, the jobs agent 156 may access information managementpolicies 148 to determine when and how to initiate and control secondarycopy and other information management operations, as will be discussedfurther.

The user interface 158 may include information processing and displaysoftware, such as a graphical user interface (“GUI”), an applicationprogram interface (“API”), or other interactive interface through whichusers and system processes can retrieve information about the status ofinformation management operations (e.g., storage operations) or issueinstructions to the information management system 100 and itsconstituent components.

The storage manager 140 may also track information that permits it toselect, designate, or otherwise identify content indices, deduplicationdatabases, or similar databases or resources or data sets within itsinformation management cell (or another cell) to be searched in responseto certain queries. Such queries may be entered by the user viainteraction with the user interface 158.

Via the user interface 158, users may optionally issue instructions tothe components in the information management system 100 regardingperformance of storage and recovery operations. For example, a user maymodify a schedule concerning the number of pending secondary copyoperations. As another example, a user may employ the GUI to view thestatus of pending storage operations or to monitor the status of certaincomponents in the information management system 100 (e.g., the amount ofcapacity left in a storage device).

In general, the management agent 154 allows multiple informationmanagement systems 100 to communicate with one another. For example, theinformation management system 100 in some cases may be one informationmanagement subsystem or “cell” of a network of multiple cells adjacentto one another or otherwise logically related in a WAN or LAN. With thisarrangement, the cells may be connected to one another throughrespective management agents 154.

For instance, the management agent 154 can provide the storage manager140 with the ability to communicate with other components within theinformation management system 100 (and/or other cells within a largerinformation management system) via network protocols and applicationprogramming interfaces (“APIs”) including, e.g., HTTP, HTTPS, FTP, REST,virtualization software APIs, cloud service provider APIs, and hostedservice provider APIs. Inter-cell communication and hierarchy isdescribed in greater detail in U.S. Pat. No. 7,035,880, which isincorporated by reference herein.

Data Agents

As discussed, a variety of different types of applications 110 canreside on a given client computing device 102, including operatingsystems, database applications, e-mail applications, and virtualmachines, just to name a few. And, as part of the as part of the processof creating and restoring secondary copies 116, the client computingdevices 102 may be tasked with processing and preparing the primary data112 from these various different applications 110. Moreover, the natureof the processing/preparation can differ across clients and applicationtypes, e.g., due to inherent structural and formatting differencesbetween applications 110.

The one or more data agent(s) 142 are therefore advantageouslyconfigured in some embodiments to assist in the performance ofinformation management operations based on the type of data that isbeing protected, at a client-specific and/or application-specific level.

The data agent 142 may be a software module or component that isgenerally responsible for managing, initiating, or otherwise assistingin the performance of information management operations. For instance,the data agent 142 may take part in performing data storage operationssuch as the copying, archiving, migrating, replicating of primary data112 stored in the primary storage device(s) 104. The data agent 142 mayreceive control information from the storage manager 140, such ascommands to transfer copies of data objects, metadata, and other payloaddata to the media agents 144.

In some embodiments, a data agent 142 may be distributed between theclient computing device 102 and storage manager 140 (and any otherintermediate components) or may be deployed from a remote location orits functions approximated by a remote process that performs some or allof the functions of data agent 142. In addition, a data agent 142 mayperform some functions provided by a media agent 144, e.g., encryptionand deduplication.

As indicated, each data agent 142 may be specialized for a particularapplication 110, and the system can employ multiple data agents 142,each of which may backup, migrate, and recover data associated with adifferent application 110. For instance, different individual dataagents 142 may be designed to handle Microsoft Exchange data, LotusNotes data, Microsoft Windows file system data, Microsoft ActiveDirectory Objects data, SQL Server data, SharePoint data, Oracledatabase data, SAP database data, virtual machines and/or associateddata, and other types of data.

A file system data agent, for example, may handle data files and/orother file system information. If a client computing device 102 has twoor more types of data, one data agent 142 may be used for each data typeto copy, archive, migrate, and restore the client computing device 102data. For example, to backup, migrate, and restore all of the data on aMicrosoft Exchange server, the client computing device 102 may use oneMicrosoft Exchange Mailbox data agent 142 to backup the Exchangemailboxes, one Microsoft Exchange Database data agent 142 to backup theExchange databases, one Microsoft Exchange Public Folder data agent 142to backup the Exchange Public Folders, and one Microsoft Windows FileSystem data agent 142 to backup the file system of the client computingdevice 102. In such embodiments, these data agents 142 may be treated asfour separate data agents 142 even though they reside on the same clientcomputing device 102.

Other embodiments may employ one or more generic data agents 142 thatcan handle and process data from two or more different applications 110,or that can handle and process multiple data types, instead of or inaddition to using specialized data agents 142. For example, one genericdata agent 142 may be used to back up, migrate and restore MicrosoftExchange Mailbox data and Microsoft Exchange Database data while anothergeneric data agent may handle Microsoft Exchange Public Folder data andMicrosoft Windows File System data.

Each data agent 142 may be configured to access data and/or metadatastored in the primary storage device(s) 104 associated with the dataagent 142 and process the data as appropriate. For example, during asecondary copy operation, the data agent 142 may arrange or assemble thedata and metadata into one or more files having a certain format (e.g.,a particular backup or archive format) before transferring the file(s)to a media agent 144 or other component. The file(s) may include a listof files or other metadata. Each data agent 142 can also assist inrestoring data or metadata to primary storage devices 104 from asecondary copy 116. For instance, the data agent 142 may operate inconjunction with the storage manager 140 and one or more of the mediaagents 144 to restore data from secondary storage device(s) 108.

Media Agents

As indicated above with respect to FIG. 1A, off-loading certainresponsibilities from the client computing devices 102 to intermediarycomponents such as the media agent(s) 144 can provide a number ofbenefits including improved client computing device 102 operation,faster secondary copy operation performance, and enhanced scalability.As one specific example which will be discussed below in further detail,the media agent 144 can act as a local cache of copied data and/ormetadata that it has stored to the secondary storage device(s) 108,providing improved restore capabilities.

Generally speaking, a media agent 144 may be implemented as a softwaremodule that manages, coordinates, and facilitates the transmission ofdata, as directed by the storage manager 140, between a client computingdevice 102 and one or more secondary storage devices 108. Whereas thestorage manager 140 controls the operation of the information managementsystem 100, the media agent 144 generally provides a portal to secondarystorage devices 108.

Media agents 144 can comprise logically and/or physically separate nodesin the information management system 100 (e.g., separate from the clientcomputing devices 102, storage manager 140, and/or secondary storagedevices 108). In addition, each media agent 144 may reside on adedicated secondary storage computing device 106 in some cases, while inother embodiments a plurality of media agents 144 reside on the samesecondary storage computing device 106.

A media agent 144 (and corresponding media agent database 152) may beconsidered to be “associated with” a particular secondary storage device108 if that media agent 144 is capable of one or more of: routing and/orstoring data to the particular secondary storage device 108,coordinating the routing and/or storing of data to the particularsecondary storage device 108, retrieving data from the particularsecondary storage device 108, and coordinating the retrieval of datafrom a particular secondary storage device 108.

While media agent(s) 144 are generally associated with one or moresecondary storage devices 108, the media agents 144 in certainembodiments are physically separate from the secondary storage devices108. For instance, the media agents 144 may reside on secondary storagecomputing devices 106 having different housings or packages than thesecondary storage devices 108. In one example, a media agent 144 resideson a first server computer and is in communication with a secondarystorage device(s) 108 residing in a separate, rack-mounted RAID-basedsystem.

In operation, a media agent 144 associated with a particular secondarystorage device 108 may instruct the secondary storage device 108 (e.g.,a tape library) to use a robotic arm or other retrieval means to load oreject a certain storage media, and to subsequently archive, migrate, orretrieve data to or from that media, e.g., for the purpose of restoringthe data to a client computing device 102. The media agent 144 maycommunicate with a secondary storage device 108 via a suitablecommunications link, such as a SCSI or Fiber Channel link.

As shown, each media agent 144 may maintain an associated media agentdatabase 152. The media agent database 152 may be stored in a disk orother storage device (not shown) that is local to the secondary storagecomputing device 106 on which the media agent 144 resides. In othercases, the media agent database 152 is stored remotely from thesecondary storage computing device 106.

The media agent database 152 can include, among other things, an index153 including data generated during secondary copy operations and otherstorage or information management operations. The index 153 provides amedia agent 144 or other component with a fast and efficient mechanismfor locating secondary copies 116 or other data stored in the secondarystorage devices 108. In one configuration, a storage manager index 150or other data structure may store data associating a client computingdevice 102 with a particular media agent 144 and/or secondary storagedevice 108, as specified in a storage policy. A media agent index 153 orother data structure associated with the particular media agent 144 mayin turn include information about the stored data.

For instance, for each secondary copy 116, the index 153 may includemetadata such as a list of the data objects (e.g., files/subdirectories,database objects, mailbox objects, etc.), a path to the secondary copy116 on the corresponding secondary storage device 108, locationinformation indicating where the data objects are stored in thesecondary storage device 108, when the data objects were created ormodified, etc. Thus, the index 153 includes metadata associated with thesecondary copies 116 that is readily available for use in storageoperations and other activities without having to be first retrievedfrom the secondary storage device 108. In yet further embodiments, someor all of the data in the index 153 may instead or additionally bestored along with the data in a secondary storage device 108, e.g., witha copy of the index 153.

Because the index 153 maintained in the database 152 may operate as acache, it can also be referred to as an index cache. In such cases,information stored in the index cache 153 typically comprises data thatreflects certain particulars about storage operations that have occurredrelatively recently. After some triggering event, such as after acertain period of time elapses, or the index cache 153 reaches aparticular size, the index cache 153 may be copied or migrated to asecondary storage device(s) 108. This information may need to beretrieved and uploaded back into the index cache 153 or otherwiserestored to a media agent 144 to facilitate retrieval of data from thesecondary storage device(s) 108. In some embodiments, the cachedinformation may include format or containerization information relatedto archives or other files stored on the storage device(s) 108. In thismanner, the index cache 153 allows for accelerated restores.

In some alternative embodiments the media agent 144 generally acts as acoordinator or facilitator of storage operations between clientcomputing devices 102 and corresponding secondary storage devices 108,but does not actually write the data to the secondary storage device108. For instance, the storage manager 140 (or the media agent 144) mayinstruct a client computing device 102 and secondary storage device 108to communicate with one another directly. In such a case the clientcomputing device 102 transmits the data directly to the secondarystorage device 108 according to the received instructions, and viceversa. In some such cases, the media agent 144 may still receive,process, and/or maintain metadata related to the storage operations.Moreover, in these embodiments, the payload data can flow through themedia agent 144 for the purposes of populating the index cache 153maintained in the media agent database 152, but not for writing to thesecondary storage device 108.

The media agent 144 and/or other components such as the storage manager140 may in some cases incorporate additional functionality, such as dataclassification, content indexing, deduplication, encryption,compression, and the like. Further details regarding these and otherfunctions are described below.

Distributed, Scalable Architecture

As described, certain functions of the information management system 100can be distributed amongst various physical and/or logical components inthe system. For instance, one or more of the storage manager 140, dataagents 142, and media agents 144 may reside on computing devices thatare physically separate from one another. This architecture can providea number of benefits.

For instance, hardware and software design choices for each distributedcomponent can be targeted to suit its particular function. The secondarycomputing devices 106 on which the media agents 144 reside can betailored for interaction with associated secondary storage devices 108and provide fast index cache operation, among other specific tasks.Similarly, the client computing device(s) 102 can be selected toeffectively service the applications 110 residing thereon, in order toefficiently produce and store primary data 112.

Moreover, in some cases, one or more of the individual components in theinformation management system 100 can be distributed to multiple,separate computing devices. As one example, for large file systems wherethe amount of data stored in the storage management database 146 isrelatively large, the management database 146 may be migrated to orotherwise reside on a specialized database server (e.g., an SQL server)separate from a server that implements the other functions of thestorage manager 140. This configuration can provide added protectionbecause the database 146 can be protected with standard databaseutilities (e.g., SQL log shipping or database replication) independentfrom other functions of the storage manager 140. The database 146 can beefficiently replicated to a remote site for use in the event of adisaster or other data loss incident at the primary site. Or thedatabase 146 can be replicated to another computing device within thesame site, such as to a higher performance machine in the event that astorage manager host device can no longer service the needs of a growinginformation management system 100.

The distributed architecture also provides both scalability andefficient component utilization. FIG. 1D shows an embodiment of theinformation management system 100 including a plurality of clientcomputing devices 102 and associated data agents 142 as well as aplurality of secondary storage computing devices 106 and associatedmedia agents 144.

Additional components can be added or subtracted based on the evolvingneeds of the information management system 100. For instance, dependingon where bottlenecks are identified, administrators can add additionalclient computing devices 102, secondary storage devices 106 (andcorresponding media agents 144), and/or secondary storage devices 108.

Moreover, each client computing device 102 in some embodiments cancommunicate with any of the media agents 144, e.g., as directed by thestorage manager 140. And each media agent 144 may be able to communicatewith any of the secondary storage devices 108, e.g., as directed by thestorage manager 140. Thus, operations can be routed to the secondarystorage devices 108 in a dynamic and highly flexible manner. Furtherexamples of scalable systems capable of dynamic storage operations areprovided in U.S. Pat. No. 7,246,207, which is incorporated by referenceherein.

In alternative configurations, certain components are not distributedand may instead reside and execute on the same computing device. Forexample, in some embodiments one or more data agents 142 and the storagemanager 140 reside on the same client computing device 102. In anotherembodiment, one or more data agents 142 and one or more media agents 144reside on a single computing device.

Exemplary Types of Information Management Operations

In order to protect and leverage stored data, the information managementsystem 100 can be configured to perform a variety of informationmanagement operations. As will be described, these operations cangenerally include secondary copy and other data movement operations,processing and data manipulation operations, and management operations.

Data Movement Operations

Data movement operations according to certain embodiments are generallyoperations that involve the copying or migration of data (e.g., payloaddata) between different locations in the information management system100. For example, data movement operations can include operations inwhich stored data is copied, migrated, or otherwise transferred fromprimary storage device(s) 104 to secondary storage device(s) 108, fromsecondary storage device(s) 108 to different secondary storage device(s)108, or from primary storage device(s) 104 to different primary storagedevice(s) 104.

Data movement operations can include by way of example, backupoperations, archive operations, information lifecycle managementoperations such as hierarchical storage management operations,replication operations (e.g., continuous data replication operations),snapshot operations, deduplication operations, single-instancingoperations, auxiliary copy operations, and the like. As will bediscussed, some of these operations involve the copying, migration orother movement of data, without actually creating multiple, distinctcopies. Nonetheless, some or all of these operations are referred to as“copy” operations for simplicity.

Backup Operations

A backup operation creates a copy of primary data 112 at a particularpoint in time. Each subsequent backup copy may be maintainedindependently of the first. Further, a backup copy in some embodimentsis stored in a backup format. This can be in contrast to the version inprimary data 112 from which the backup copy is derived, and which mayinstead be stored in a native format of the source application(s) 110.In various cases, backup copies can be stored in a format in which thedata is compressed, encrypted, deduplicated, and/or otherwise modifiedfrom the original application format. For example, a backup copy may bestored in a backup format that facilitates compression and/or efficientlong-term storage.

Backup copies can have relatively long retention periods as compared toprimary data 112, and may be stored on media with slower retrieval timesthan primary data 112 and certain other types of secondary copies 116.On the other hand, backups may have relatively shorter retention periodsthan some other types of secondary copies 116, such as archive copies(described below). Backups may sometimes be stored at on offsitelocation.

Backup operations can include full, synthetic or incremental backups. Afull backup in some embodiments is generally a complete image of thedata to be protected. However, because full backup copies can consume arelatively large amount of storage, it can be useful to use a fullbackup copy as a baseline and only store changes relative to the fullbackup copy for subsequent backup copies.

For instance, a differential backup operation (or cumulative incrementalbackup operation) tracks and stores changes that have occurred since thelast full backup. Differential backups can grow quickly in size, but canprovide relatively efficient restore times because a restore can becompleted in some cases using only the full backup copy and the latestdifferential copy.

An incremental backup operation generally tracks and stores changessince the most recent backup copy of any type, which can greatly reducestorage utilization. In some cases, however, restore times can berelatively long in comparison to full or differential backups becausecompleting a restore operation may involve accessing a full backup inaddition to multiple incremental backups.

Any of the above types of backup operations can be at the file-level,e.g., where the information management system 100 generally trackschanges to files at the file-level, and includes copies of files in thebackup copy. In other cases, block-level backups are employed, wherefiles are broken into constituent blocks, and changes are tracked at theblock-level. Upon restore, the information management system 100reassembles the blocks into files in a transparent fashion.

Far less data may actually be transferred and copied to the secondarystorage devices 108 during a block-level copy than during a file-levelcopy, resulting in faster execution times. However, when restoring ablock-level copy, the process of locating constituent blocks cansometimes result in longer restore times as compared to file-levelbackups. Similar to backup operations, the other types of secondary copyoperations described herein can also be implemented at either thefile-level or the block-level.

Archive Operations

Because backup operations generally involve maintaining a version of thecopied data in primary data 112 and also maintaining backup copies insecondary storage device(s) 108, they can consume significant storagecapacity. To help reduce storage consumption, an archive operationaccording to certain embodiments creates a secondary copy 116 by bothcopying and removing source data. Or, seen another way, archiveoperations can involve moving some or all of the source data to thearchive destination. Thus, data satisfying criteria for removal (e.g.,data of a threshold age or size) from the source copy may be removedfrom source storage. Archive copies are sometimes stored in an archiveformat or other non-native application format. The source data may beprimary data 112 or a secondary copy 116, depending on the situation. Aswith backup copies, archive copies can be stored in a format in whichthe data is compressed, encrypted, deduplicated, and/or otherwisemodified from the original application format.

In addition, archive copies may be retained for relatively long periodsof time (e.g., years) and, in some cases, are never deleted. Archivecopies are generally retained for longer periods of time than backupcopies, for example. In certain embodiments, archive copies may be madeand kept for extended periods in order to meet compliance regulations.

Moreover, when primary data 112 is archived, in some cases the archivedprimary data 112 or a portion thereof is deleted when creating thearchive copy. Thus, archiving can serve the purpose of freeing up spacein the primary storage device(s) 104. Similarly, when a secondary copy116 is archived, the secondary copy 116 may be deleted, and an archivecopy can therefore serve the purpose of freeing up space in secondarystorage device(s) 108. In contrast, source copies often remain intactwhen creating backup copies.

Snapshot Operations

Snapshot operations can provide a relatively lightweight, efficientmechanism for protecting data. From an end-user viewpoint, a snapshotmay be thought of as an “instant” image of the primary data 112 at agiven point in time. In one embodiment, a snapshot may generally capturethe directory structure of an object in primary data 112 such as a fileor volume or other data set at a particular moment in time and may alsopreserve file attributes and contents. A snapshot in some cases iscreated relatively quickly, e.g., substantially instantly, using aminimum amount of file space, but may still function as a conventionalfile system backup.

A snapshot copy in many cases can be made quickly and withoutsignificantly impacting primary computing resources because largeamounts of data need not be copied or moved. In some embodiments, asnapshot may exist as a virtual file system, parallel to the actual filesystem. Users in some cases gain read-only access to the record of filesand directories of the snapshot. By electing to restore primary data 112from a snapshot taken at a given point in time, users may also returnthe current file system to the state of the file system that existedwhen the snapshot was taken.

Some types of snapshots do not actually create another physical copy ofall the data as it existed at the particular point in time, but maysimply create pointers that are able to map files and directories tospecific memory locations (e.g., disk blocks) where the data resides, asit existed at the particular point in time. For example, a snapshot copymay include a set of pointers derived from the file system or anapplication. Each pointer points to a respective stored data block, socollectively, the set of pointers reflect the storage location and stateof the data object (e.g., file(s) or volume(s) or data set(s)) at aparticular point in time when the snapshot copy was created.

In some embodiments, once a snapshot has been taken, subsequent changesto the file system typically do not overwrite the blocks in use at thetime of the snapshot. Therefore, the initial snapshot may use only asmall amount of disk space needed to record a mapping or other datastructure representing or otherwise tracking the blocks that correspondto the current state of the file system. Additional disk space isusually required only when files and directories are actually modifiedlater. Furthermore, when files are modified, typically only the pointerswhich map to blocks are copied, not the blocks themselves. In someembodiments, for example in the case of “copy-on-write” snapshots, whena block changes in primary storage, the block is copied to secondarystorage or cached in primary storage before the block is overwritten inprimary storage. The snapshot mapping of file system data is alsoupdated to reflect the changed block(s) at that particular point intime. In some other cases, a snapshot includes a full physical copy ofall or substantially all of the data represented by the snapshot.Further examples of snapshot operations are provided in U.S. Pat. No.7,529,782, which is incorporated by reference herein.

Replication Operations

Another type of secondary copy operation is a replication operation.Some types of secondary copies 116 are used to periodically captureimages of primary data 112 at particular points in time (e.g., backups,archives, and snapshots). However, it can also be useful for recoverypurposes to protect primary data 112 in a more continuous fashion, byreplicating the primary data 112 substantially as changes occur. In somecases a replication copy can be a mirror copy, for instance, wherechanges made to primary data 112 are mirrored to another location (e.g.,to secondary storage device(s) 108). By copying each write operation tothe replication copy, two storage systems are kept synchronized orsubstantially synchronized so that they are virtually identical atapproximately the same time. Where entire disk volumes are mirrored,however, mirroring can require significant amount of storage space andutilizes a large amount of processing resources.

According to some embodiments storage operations are performed onreplicated data that represents a recoverable state, or “known goodstate” of a particular application running on the source system. Forinstance, in certain embodiments, known good replication copies may beviewed as copies of primary data 112. This feature allows the system todirectly access, copy, restore, backup or otherwise manipulate thereplication copies as if the data was the “live”, primary data 112. Thiscan reduce access time, storage utilization, and impact on sourceapplications 110, among other benefits.

Based on known good state information, the information management system100 can replicate sections of application data that represent arecoverable state rather than rote copying of blocks of data. Examplesof compatible replication operations (e.g., continuous data replication)are provided in U.S. Pat. No. 7,617,262, which is incorporated byreference herein.

Deduplication/Single-Instancing Operations

Another type of data movement operation is deduplication, which isuseful to reduce the amount of data within the system. For instance,some or all of the above-described secondary storage operations caninvolve deduplication in some fashion. New data is read, broken downinto blocks (e.g., sub-file level blocks) of a selected granularity,compared with blocks that are already stored, and only the new blocksare stored. Blocks that already exist are represented as pointers to thealready stored data.

In order to stream-line the comparison process, the informationmanagement system 100 may calculate and/or store signatures (e.g.,hashes) corresponding to the individual data blocks and compare thehashes instead of comparing entire data blocks. In some cases, only asingle instance of each element is stored, and deduplication operationsmay therefore be referred to interchangeably as “single-instancing”operations. Depending on the implementation, however, deduplication orsingle-instancing operations can store more than one instance of certaindata blocks, but nonetheless significantly reduce data redundancy.Moreover, single-instancing in some cases is distinguished fromdeduplication as a process of analyzing and reducing data at the filelevel, rather than the sub-file level.

Depending on the embodiment, deduplication blocks can be of fixed orvariable length. Using variable length blocks can provide enhanceddeduplication by responding to changes in the data stream, but caninvolve complex processing. In some cases, the information managementsystem 100 utilizes a technique for dynamically aligning deduplicationblocks (e.g., fixed-length blocks) based on changing content in the datastream, as described in U.S. Pat. No. 8,364,652, which is incorporatedby reference herein.

The information management system 100 can perform deduplication in avariety of manners at a variety of locations in the informationmanagement system 100. For instance, in some embodiments, theinformation management system 100 implements “target-side” deduplicationby deduplicating data (e.g., secondary copies 116) stored in thesecondary storage devices 108. In some such cases, the media agents 144are generally configured to manage the deduplication process. Forinstance, one or more of the media agents 144 maintain a correspondingdeduplication database that stores deduplication information (e.g.,datablock signatures). Examples of such a configuration are provided inU.S. Pat. Pub. No. 2012/0150826, which is incorporated by referenceherein. Deduplication can also be performed on the “source-side” (or“client-side”), e.g., to reduce the amount of traffic between the mediaagents 144 and the client computing device(s) 102 and/or reduceredundant data stored in the primary storage devices 104. Examples ofsuch deduplication techniques are provided in U.S. Pat. Pub. No.2012/0150818, which is incorporated by reference herein.

Information Lifecycle Management and Hierarchical Storage ManagementOperations

In some embodiments, files and other data over their lifetime move frommore expensive, quick access storage to less expensive, slower accessstorage. Operations associated with moving data through various tiers ofstorage are sometimes referred to as information lifecycle management(ILM) operations.

One type of ILM operation is a hierarchical storage management (HSM)operation. A HSM operation is generally an operation for automaticallymoving data between classes of storage devices, such as betweenhigh-cost and low-cost storage devices. For instance, an HSM operationmay involve movement of data from primary storage devices 104 tosecondary storage devices 108, or between tiers of secondary storagedevices 108. With each tier, the storage devices may be progressivelyrelatively cheaper, have relatively slower access/restore times, etc.For example, movement of data between tiers may occur as data becomesless important over time.

In some embodiments, an HSM operation is similar to an archive operationin that creating an HSM copy may (though not always) involve deletingsome of the source data. For example, an HSM copy may include data fromprimary data 112 or a secondary copy 116 that is larger than a givensize threshold or older than a given age threshold and that is stored ina backup format.

Often, and unlike some types of archive copies, HSM data that is removedor aged from the source copy is replaced by a logical reference pointeror stub. The reference pointer or stub can be stored in the primarystorage device 104 to replace the deleted data in primary data 112 (orother source copy) and to point to or otherwise indicate the newlocation in a secondary storage device 108.

According to one example, files are generally moved between higher andlower cost storage depending on how often the files are accessed. When auser requests access to the HSM data that has been removed or migrated,the information management system 100 uses the stub to locate the dataand often make recovery of the data appear transparent, even though theHSM data may be stored at a location different from the remaining sourcedata. The stub may also include some metadata associated with thecorresponding data, so that a file system and/or application can providesome information about the data object and/or a limited-functionalityversion (e.g., a preview) of the data object.

An HSM copy may be stored in a format other than the native applicationformat (e.g., where the data is compressed, encrypted, deduplicated,and/or otherwise modified from the original application format). In somecases, copies which involve the removal of data from source storage andthe maintenance of stub or other logical reference information on sourcestorage may be referred to generally as “on-line archive copies”. On theother hand, copies which involve the removal of data from source storagewithout the maintenance of stub or other logical reference informationon source storage may be referred to as “off-line archive copies”.

Auxiliary Copy and Disaster Recovery Operations

An auxiliary copy is generally a copy operation in which a copy iscreated of an existing secondary copy 116. For instance, an initial or“primary” secondary copy 116 may be generated using or otherwise bederived from primary data 112, whereas an auxiliary copy is generatedfrom the initial secondary copy 116. Auxiliary copies can be used tocreate additional standby copies of data and may reside on differentsecondary storage devices 108 than initial secondary copies 116. Thus,auxiliary copies can be used for recovery purposes if initial secondarycopies 116 become unavailable. Exemplary compatible auxiliary copytechniques are described in further detail in U.S. Pat. No. 8,230,195,which is incorporated by reference herein.

The information management system 100 may also perform disaster recoveryoperations that make or retain disaster recovery copies, often assecondary, high-availability disk copies. The information managementsystem 100 may create secondary disk copies and store the copies atdisaster recovery locations using auxiliary copy or replicationoperations, such as continuous data replication technologies. Dependingon the particular data protection goals, disaster recovery locations canbe remote from the client computing devices 102 and primary storagedevices 104, remote from some or all of the secondary storage devices108, or both.

Data Processing and Manipulation Operations

As indicated, the information management system 100 can also beconfigured to implement certain data manipulation operations, whichaccording to certain embodiments are generally operations involving theprocessing or modification of stored data. Some data manipulationoperations include content indexing operations and classificationoperations can be useful in leveraging the data under management toprovide enhanced search and other features. Other data manipulationoperations such as compression and encryption can provide data reductionand security benefits, respectively.

Data manipulation operations can be different than data movementoperations in that they do not necessarily involve the copying,migration or other transfer of data (e.g., primary data 112 or secondarycopies 116) between different locations in the system. For instance,data manipulation operations may involve processing (e.g., offlineprocessing) or modification of already stored primary data 112 and/orsecondary copies 116. However, in some embodiments data manipulationoperations are performed in conjunction with data movement operations.As one example, the information management system 100 may encrypt datawhile performing an archive operation.

Content Indexing

In some embodiments, the information management system 100 “contentindexes” data stored within the primary data 112 and/or secondary copies116, providing enhanced search capabilities for data discovery and otherpurposes. The content indexing can be used to identify files or otherdata objects having pre-defined content (e.g., user-defined keywords orphrases), metadata (e.g., email metadata such as “to”, “from”, “cc”,“bcc”, attachment name, received time, etc.).

The information management system 100 generally organizes and cataloguesthe results in a content index, which may be stored within the mediaagent database 152, for example. The content index can also include thestorage locations of (or pointer references to) the indexed data in theprimary data 112 or secondary copies 116, as appropriate. The resultsmay also be stored, in the form of a content index database orotherwise, elsewhere in the information management system 100 (e.g., inthe primary storage devices 104, or in the secondary storage device108). Such index data provides the storage manager 140 or anothercomponent with an efficient mechanism for locating primary data 112and/or secondary copies 116 of data objects that match particularcriteria.

For instance, search criteria can be specified by a user through userinterface 158 of the storage manager 140. In some cases, the informationmanagement system 100 analyzes data and/or metadata in secondary copies116 to create an “off-line” content index, without significantlyimpacting the performance of the client computing devices 102. Dependingon the embodiment, the system can also implement “on-line” contentindexing, e.g., of primary data 112. Examples of compatible contentindexing techniques are provided in U.S. Pat. No. 8,170,995, which isincorporated by reference herein.

Classification Operations—Metabase

In order to help leverage the data stored in the information managementsystem 100, one or more components can be configured to scan data and/orassociated metadata for classification purposes to populate a metabaseof information. Such scanned, classified data and/or metadata may beincluded in a separate database and/or on a separate storage device fromprimary data 112 (and/or secondary copies 116), such that metabaserelated operations do not significantly impact performance on othercomponents in the information management system 100.

In other cases, the metabase(s) may be stored along with primary data112 and/or secondary copies 116. Files or other data objects can beassociated with user-specified identifiers (e.g., tag entries) in themedia agent 144 (or other indices) to facilitate searches of stored dataobjects. Among a number of other benefits, the metabase can also allowefficient, automatic identification of files or other data objects toassociate with secondary copy or other information management operations(e.g., in lieu of scanning an entire file system). Examples ofcompatible metabases and data classification operations are provided inU.S. Pat. Nos. 8,229,954 and 7,747,579, which are incorporated byreference herein.

Encryption Operations

The information management system 100 in some cases is configured toprocess data (e.g., files or other data objects, secondary copies 116,etc.), according to an appropriate encryption algorithm (e.g., Blowfish,Advanced Encryption Standard [AES], Triple Data Encryption Standard[3-DES], etc.) to limit access and provide data security in theinformation management system 100.

The information management system 100 in some cases encrypts the data atthe client level, such that the client computing devices 102 (e.g., thedata agents 142) encrypt the data prior to forwarding the data to othercomponents, e.g., before sending the data media agents 144 during asecondary copy operation. In such cases, the client computing device 102may maintain or have access to an encryption key or passphrase fordecrypting the data upon restore. Encryption can also occur whencreating copies of secondary copies, e.g., when creating auxiliarycopies. In yet further embodiments, the secondary storage devices 108can implement built-in, high performance hardware encryption.

Management Operations

Certain embodiments leverage the integrated, ubiquitous nature of theinformation management system 100 to provide useful system-widemanagement functions. As two non-limiting examples, the informationmanagement system 100 can be configured to implement operationsmanagement and e-discovery functions.

Operations management can generally include monitoring and managing thehealth and performance of information management system 100 by, withoutlimitation, performing error tracking, generating granularstorage/performance metrics (e.g., job success/failure information,deduplication efficiency, etc.), generating storage modeling and costinginformation, and the like.

Such information can be provided to users via the user interface 158 ina single, integrated view. For instance, the integrated user interface158 can include an option to show a “virtual view” of the system thatgraphically depicts the various components in the system usingappropriate icons. The operations management functionality canfacilitate planning and decision-making. For example, in someembodiments, a user may view the status of some or all jobs as well asthe status of each component of the information management system 100.Users may then plan and make decisions based on this data. For instance,a user may view high-level information regarding storage operations forthe information management system 100, such as job status, componentstatus, resource status (e.g., network pathways, etc.), and otherinformation. The user may also drill down or use other means to obtainmore detailed information regarding a particular component, job, or thelike.

In some cases the information management system 100 alerts a user suchas a system administrator when a particular resource is unavailable orcongested. For example, a particular primary storage device 104 orsecondary storage device 108 might be full or require additionalcapacity. Or a component may be unavailable due to hardware failure,software problems, or other reasons. In response, the informationmanagement system 100 may suggest solutions to such problems when theyoccur (or provide a warning prior to occurrence). For example, thestorage manager 140 may alert the user that a secondary storage device108 is full or otherwise congested. The storage manager 140 may thensuggest, based on job and data storage information contained in itsdatabase 146, an alternate secondary storage device 108.

Other types of corrective actions may include suggesting an alternatedata path to a particular primary or secondary storage device 104, 108,or dividing data to be stored among various available primary orsecondary storage devices 104, 108 as a load balancing measure or tootherwise optimize storage or retrieval time. Such suggestions orcorrective actions may be performed automatically, if desired. Furtherexamples of some compatible operations management techniques and ofinterfaces providing an integrated view of an information managementsystem are provided in U.S. Pat. No. 7,343,453, which is incorporated byreference herein. In some embodiments, the storage manager 140implements the operations management functions described herein.

The information management system 100 can also be configured to performsystem-wide e-discovery operations in some embodiments. In general,e-discovery operations provide a unified collection and searchcapability for data in the system, such as data stored in the secondarystorage devices 108 (e.g., backups, archives, or other secondary copies116). For example, the information management system 100 may constructand maintain a virtual repository for data stored in the informationmanagement system 100 that is integrated across source applications 110,different storage device types, etc. According to some embodiments,e-discovery utilizes other techniques described herein, such as dataclassification and/or content indexing.

Information Management Policies

As indicated previously, an information management policy 148 caninclude a data structure or other information source that specifies aset of parameters (e.g., criteria and rules) associated with secondarycopy or other information management operations.

One type of information management policy 148 is a storage policy.According to certain embodiments, a storage policy generally comprises alogical container that defines (or includes information sufficient todetermine) one or more of the following items: (1) what data will beassociated with the storage policy; (2) a destination to which the datawill be stored; (3) datapath information specifying how the data will becommunicated to the destination; (4) the type of storage operation to beperformed; and (5) retention information specifying how long the datawill be retained at the destination.

Data associated with a storage policy can be logically organized intogroups, which can be referred to as “sub-clients”. A sub-client mayrepresent static or dynamic associations of portions of a data volume.Sub-clients may represent mutually exclusive portions. Thus, in certainembodiments, a portion of data may be given a label and the associationis stored as a static entity in an index, database or other storagelocation.

Sub-clients may also be used as an effective administrative scheme oforganizing data according to data type, department within theenterprise, storage preferences, or the like. Depending on theconfiguration, sub-clients can correspond to files, folders, virtualmachines, databases, etc. In one exemplary scenario, an administratormay find it preferable to separate e-mail data from financial data usingtwo different sub-clients.

A storage policy can define where data is stored by specifying a targetor destination storage device (or group of storage devices). Forinstance, where the secondary storage device 108 includes a group ofdisk libraries, the storage policy may specify a particular disk libraryfor storing the sub-clients associated with the policy. As anotherexample, where the secondary storage devices 108 include one or moretape libraries, the storage policy may specify a particular tape libraryfor storing the sub-clients associated with the storage policy, and mayalso specify a drive pool and a tape pool defining a group of tapedrives and a group of tapes, respectively, for use in storing thesub-client data.

Datapath information can also be included in the storage policy. Forinstance, the storage policy may specify network pathways and componentsto utilize when moving the data to the destination storage device(s). Insome embodiments, the storage policy specifies one or more media agents144 for conveying data (e.g., one or more sub-clients) associated withthe storage policy between the source (e.g., one or more host clientcomputing devices 102) and destination (e.g., a particular targetsecondary storage device 108).

A storage policy can also specify the type(s) of operations associatedwith the storage policy, such as a backup, archive, snapshot, auxiliarycopy, or the like. Retention information can specify how long the datawill be kept, depending on organizational needs (e.g., a number of days,months, years, etc.)

The information management policies 148 may also include one or morescheduling policies specifying when and how often to perform operations.Scheduling information may specify with what frequency (e.g., hourly,weekly, daily, event-based, etc.) or under what triggering conditionssecondary copy or other information management operations will takeplace. Scheduling policies in some cases are associated with particularcomponents, such as particular sub-clients, client computing device 102,and the like. In one configuration, a separate scheduling policy ismaintained for particular sub-clients on a client computing device 102.The scheduling policy specifies that those sub-clients are to be movedto secondary storage devices 108 every hour according to storagepolicies associated with the respective sub-clients.

When adding a new client computing device 102, administrators canmanually configure information management policies 148 and/or othersettings, e.g., via the user interface 158. However, this can be aninvolved process resulting in delays, and it may be desirable to begindata protecting operations quickly.

Thus, in some embodiments, the information management system 100automatically applies a default configuration to client computing device102. As one example, when a data agent(s) 142 is installed on a clientcomputing devices 102, the installation script may register the clientcomputing device 102 with the storage manager 140, which in turn appliesthe default configuration to the new client computing device 102. Inthis manner, data protection operations can begin substantiallyimmediately. The default configuration can include a default storagepolicy, for example, and can specify any appropriate informationsufficient to begin data protection operations. This can include a typeof data protection operation, scheduling information, a target secondarystorage device 108, data path information (e.g., a particular mediaagent 144), and the like.

Other types of information management policies 148 are possible. Forinstance, the information management policies 148 can also include oneor more audit or security policies. An audit policy is a set ofpreferences, rules and/or criteria that protect sensitive data in theinformation management system 100. For example, an audit policy maydefine “sensitive objects” as files or objects that contain particularkeywords (e.g. “confidential,” or “privileged”) and/or are associatedwith particular keywords (e.g., in metadata) or particular flags (e.g.,in metadata identifying a document or email as personal, confidential,etc.).

An audit policy may further specify rules for handling sensitiveobjects. As an example, an audit policy may require that a reviewerapprove the transfer of any sensitive objects to a cloud storage site,and that if approval is denied for a particular sensitive object, thesensitive object should be transferred to a local storage device 104instead. To facilitate this approval, the audit policy may furtherspecify how a secondary storage computing device 106 or other systemcomponent should notify a reviewer that a sensitive object is slated fortransfer.

In some implementations, the information management policies 148 mayinclude one or more provisioning policies. A provisioning policy caninclude a set of preferences, priorities, rules, and/or criteria thatspecify how clients 102 (or groups thereof) may utilize systemresources, such as available storage on cloud storage and/or networkbandwidth. A provisioning policy specifies, for example, data quotas forparticular client computing devices 102 (e.g. a number of gigabytes thatcan be stored monthly, quarterly or annually). The storage manager 140or other components may enforce the provisioning policy. For instance,the media agents 144 may enforce the policy when transferring data tosecondary storage devices 108. If a client computing device 102 exceedsa quota, a budget for the client computing device 102 (or associateddepartment) is adjusted accordingly or an alert may trigger.

While the above types of information management policies 148 have beendescribed as separate policies, one or more of these can be generallycombined into a single information management policy 148. For instance,a storage policy may also include or otherwise be associated with one ormore scheduling, audit, or provisioning policies. Moreover, whilestorage policies are typically associated with moving and storing data,other policies may be associated with other types of informationmanagement operations. The following is a non-exhaustive list of itemsthe information management policies 148 may specify:

-   -   schedules or other timing information, e.g., specifying when        and/or how often to perform information management operations;    -   the type of secondary copy 116 and/or secondary copy format        (e.g., snapshot, backup, archive, HSM, etc.);    -   a location or a class or quality of storage for storing        secondary copies 116 (e.g., one or more particular secondary        storage devices 108);    -   preferences regarding whether and how to encrypt, compress,        deduplicate, or otherwise modify or transform secondary copies        116;    -   which system components and/or network pathways (e.g., preferred        media agents 144) should be used to perform secondary storage        operations;    -   resource allocation between different computing devices or other        system components used in performing information management        operations (e.g., bandwidth allocation, available storage        capacity, etc.);    -   whether and how to synchronize or otherwise distribute files or        other data objects across multiple computing devices or hosted        services; and    -   retention information specifying the length of time primary data        112 and/or secondary copies 116 should be retained, e.g., in a        particular class or tier of storage devices, or within the        information management system 100.

Policies can additionally specify or depend on a variety of historicalor current criteria that may be used to determine which rules to applyto a particular data object, system component, or information managementoperation, such as:

-   -   frequency with which primary data 112 or a secondary copy 116 of        a data object or metadata has been or is predicted to be used,        accessed, or modified;    -   time-related factors (e.g., aging information such as time since        the creation or modification of a data object);    -   deduplication information (e.g., hashes, data blocks,        deduplication block size, deduplication efficiency or other        metrics);    -   an estimated or historic usage or cost associated with different        components (e.g., with secondary storage devices 108);    -   the identity of users, applications 110, client computing        devices 102 and/or other computing devices that created,        accessed, modified, or otherwise utilized primary data 112 or        secondary copies 116;    -   a relative sensitivity (e.g., confidentiality) of a data object,        e.g., as determined by its content and/or metadata;    -   the current or historical storage capacity of various storage        devices;    -   the current or historical network capacity of network pathways        connecting various components within the storage operation cell;    -   access control lists or other security information; and    -   the content of a particular data object (e.g., its textual        content) or of metadata associated with the data object.        Exemplary Storage Policy and Secondary Storage Operations

FIG. 1E shows a data flow data diagram depicting performance of storageoperations by an embodiment of an information management system 100,according to an exemplary data storage policy 148A. The informationmanagement system 100 includes a storage manger 140, a client computingdevice 102 having a file system data agent 142A and an email data agent142B residing thereon, a primary storage device 104, two media agents144A, 144B, and two secondary storage devices 108A, 108B: a disk library108A and a tape library 108B. As shown, the primary storage device 104includes primary data 112A, 1128 associated with a file systemsub-client and an email sub-client, respectively.

As indicated by the dashed box, the second media agent 144B and the tapelibrary 108B are “off-site”, and may therefore be remotely located fromthe other components in the information management system 100 (e.g., ina different city, office building, etc.). In this manner, informationstored on the tape library 108B may provide protection in the event of adisaster or other failure.

The file system sub-client and its associated primary data 112A incertain embodiments generally comprise information generated by the filesystem and/or operating system of the client computing device 102, andcan include, for example, file system data (e.g., regular files, filetables, mount points, etc.), operating system data (e.g., registries,event logs, etc.), and the like. The e-mail sub-client, on the otherhand, and its associated primary data 1128, include data generated by ane-mail client application operating on the client computing device 102,and can include mailbox information, folder information, emails,attachments, associated database information, and the like. As describedabove, the sub-clients can be logical containers, and the data includedin the corresponding primary data 112A, 1128 may or may not be storedcontiguously.

The exemplary storage policy 148A includes a backup copy rule set 160, adisaster recovery copy rule set 162, and a compliance copy rule set 164.The backup copy rule set 160 specifies that it is associated with a filesystem sub-client 166 and an email sub-client 168. Each of thesesub-clients 166, 168 are associated with the particular client computingdevice 102. The backup copy rule set 160 further specifies that thebackup operation will be written to the disk library 108A, anddesignates a particular media agent 144A to convey the data to the disklibrary 108A. Finally, the backup copy rule set 160 specifies thatbackup copies created according to the rule set 160 are scheduled to begenerated on an hourly basis and to be retained for 30 days. In someother embodiments, scheduling information is not included in the storagepolicy 148A, and is instead specified by a separate scheduling policy.

The disaster recovery copy rule set 162 is associated with the same twosub-clients 166, 168. However, the disaster recovery copy rule set 162is associated with the tape library 108B, unlike the backup copy ruleset 160. Moreover, the disaster recovery copy rule set 162 specifiesthat a different media agent 144B than the media agent 144A associatedwith the backup copy rule set 160 will be used to convey the data to thetape library 108B. As indicated, disaster recovery copies createdaccording to the rule set 162 will be retained for 60 days, and will begenerated on a daily basis. Disaster recovery copies generated accordingto the disaster recovery copy rule set 162 can provide protection in theevent of a disaster or other data-loss event that would affect thebackup copy 116A maintained on the disk library 108A.

The compliance copy rule set 164 is only associated with the emailsub-client 166, and not the file system sub-client 168. Compliancecopies generated according to the compliance copy rule set 164 willtherefore not include primary data 112A from the file system sub-client166. For instance, the organization may be under an obligation to storemaintain copies of email data for a particular period of time (e.g., 10years) to comply with state or federal regulations, while similarregulations do not apply to the file system data. The compliance copyrule set 164 is associated with the same tape library 108B and mediaagent 144B as the disaster recovery copy rule set 162, although adifferent storage device or media agent could be used in otherembodiments. Finally, the compliance copy rule set 164 specifies thatcopies generated under the compliance copy rule set 164 will be retainedfor 10 years, and will be generated on a quarterly basis.

At step 1, the storage manager 140 initiates a backup operationaccording to the backup copy rule set 160. For instance, a schedulingservice running on the storage manager 140 accesses schedulinginformation from the backup copy rule set 160 or a separate schedulingpolicy associated with the client computing device 102, and initiates abackup copy operation on an hourly basis. Thus, at the scheduled timeslot the storage manager 140 sends instructions to the client computingdevice 102 to begin the backup operation.

At step 2, the file system data agent 142A and the email data agent 142Bresiding on the client computing device 102 respond to the instructionsreceived from the storage manager 140 by accessing and processing theprimary data 112A, 112B involved in the copy operation from the primarystorage device 104. Because the operation is a backup copy operation,the data agent(s) 142A, 142B may format the data into a backup format orotherwise process the data.

At step 3, the client computing device 102 communicates the retrieved,processed data to the first media agent 144A, as directed by the storagemanager 140, according to the backup copy rule set 160. In some otherembodiments, the information management system 100 may implement aload-balancing, availability-based, or other appropriate algorithm toselect from the available set of media agents 144A, 144B. Regardless ofthe manner the media agent 144A is selected, the storage manager 140 mayfurther keep a record in the storage manager database 140 of theassociation between the selected media agent 144A and the clientcomputing device 102 and/or between the selected media agent 144A andthe backup copy 116A.

The target media agent 144A receives the data from the client computingdevice 102, and at step 4 conveys the data to the disk library 108A tocreate the backup copy 116A, again at the direction of the storagemanager 140 and according to the backup copy rule set 160. The secondarystorage device 108A can be selected in other ways. For instance, themedia agent 144A may have a dedicated association with a particularsecondary storage device(s), or the storage manager 140 or media agent144A may select from a plurality of secondary storage devices, e.g.,according to availability, using one of the techniques described in U.S.Pat. No. 7,246,207, which is incorporated by reference herein.

The media agent 144A can also update its index 153 to include dataand/or metadata related to the backup copy 116A, such as informationindicating where the backup copy 116A resides on the disk library 108A,data and metadata for cache retrieval, etc. After the 30 day retentionperiod expires, the storage manager 140 instructs the media agent 144Ato delete the backup copy 116A from the disk library 108A.

At step 5, the storage manager 140 initiates the creation of a disasterrecovery copy 1168 according to the disaster recovery copy rule set 162.For instance, at step 6, based on instructions received from the storagemanager 140 at step 5, the specified media agent 144B retrieves the mostrecent backup copy 116A from the disk library 108A.

At step 7, again at the direction of the storage manager 140 and asspecified in the disaster recovery copy rule set 162, the media agent144B uses the retrieved data to create a disaster recovery copy 1168 onthe tape library 108B. In some cases, the disaster recovery copy 1168 isa direct, mirror copy of the backup copy 116A, and remains in the backupformat. In other embodiments, the disaster recovery copy 116C may begenerated in some other manner, such as by using the primary data 112A,1128 from the storage device 104 as source data. The disaster recoverycopy operation is initiated once a day and the disaster recovery copies116A are deleted after 60 days.

At step 8, the storage manager 140 initiates the creation of acompliance copy 116C, according to the compliance copy rule set 164. Forinstance, the storage manager 140 instructs the media agent 144B tocreate the compliance copy 116C on the tape library 108B at step 9, asspecified in the compliance copy rule set 164. In the example, thecompliance copy 116C is generated using the disaster recovery copy 1168.In other embodiments, the compliance copy 116C is instead generatedusing either the primary data 1128 corresponding to the email sub-clientor using the backup copy 116A from the disk library 108A as source data.As specified, compliance copies 116C are created quarterly, and aredeleted after ten years.

While not shown in FIG. 1E, at some later point in time, a restoreoperation can be initiated involving one or more of the secondary copies116A, 1168, 116C. As one example, a user may manually initiate a restoreof the backup copy 116A by interacting with the user interface 158 ofthe storage manager 140. The storage manager 140 then accesses data inits index 150 (and/or the respective storage policy 148A) associatedwith the selected backup copy 116A to identify the appropriate mediaagent 144A and/or secondary storage device 116A.

In other cases, a media agent may be selected for use in the restoreoperation based on a load balancing algorithm, an availability basedalgorithm, or other criteria. The selected media agent 144A retrievesthe data from the disk library 108A. For instance, the media agent 144Amay access its index 153 to identify a location of the backup copy 116Aon the disk library 108A, or may access location information residing onthe disk 108A itself.

When the backup copy 116A was recently created or accessed, the mediaagent 144A accesses a cached version of the backup copy 116A residing inthe media agent index 153, without having to access the disk library108A for some or all of the data. Once it has retrieved the backup copy116A, the media agent 144A communicates the data to the source clientcomputing device 102. Upon receipt, the file system data agent 142A andthe email data agent 142B may unpackage (e.g., restore from a backupformat to the native application format) the data in the backup copy116A and restore the unpackaged data to the primary storage device 104.

Exemplary Secondary Copy Formatting

The formatting and structure of secondary copies 116 can vary, dependingon the embodiment. In some cases, secondary copies 116 are formatted asa series of logical data units or “chunks” (e.g., 512 MB, 1 GB, 2 GB, 4GB, or 8 GB chunks). This can facilitate efficient communication andwriting to secondary storage devices 108, e.g., according to resourceavailability. For example, a single secondary copy 116 may be written ona chunk-by-chunk basis to a single secondary storage device 108 oracross multiple secondary storage devices 108. In some cases, users canselect different chunk sizes, e.g., to improve throughput to tapestorage devices.

Generally, each chunk can include a header and a payload. The payloadcan include files (or other data units) or subsets thereof included inthe chunk, whereas the chunk header generally includes metadata relatingto the chunk, some or all of which may be derived from the payload. Forexample, during a secondary copy operation, the media agent 144, storagemanager 140, or other component may divide the associated files intochunks and generate headers for each chunk by processing the constituentfiles.

The headers can include a variety of information such as fileidentifier(s), volume(s), offset(s), or other information associatedwith the payload data items, a chunk sequence number, etc. Importantly,in addition to being stored with the secondary copy 116 on the secondarystorage device 108, the chunk headers can also be stored to the index153 of the associated media agent(s) 144 and/or the storage managerindex 150. This is useful in some cases for providing faster processingof secondary copies 116 during restores or other operations. In somecases, once a chunk is successfully transferred to a secondary storagedevice 108, the secondary storage device 108 returns an indication ofreceipt, e.g., to the media agent 144 and/or storage manager 140, whichmay update their respective indexes 150, 153 accordingly.

During restore, chunks may be processed (e.g., by the media agent 144)according to the information in the chunk header to reassemble thefiles. Additional information relating to chunks can be found in U.S.Pat. No. 8,156,086, which is incorporated by reference herein.

Lightweight Mounting of a Secondary Copy of File System DataIntroduction

When searching through a secondary copy of production data, such as aback up, archive, or snapshot copy, for specific data objects, it may bebeneficial to be able to view and browse the layout of a file systemthat organizes the secondary copy. Typical systems may allow a user toview the layout of a file system that organizes the secondary copies bymounting the entire file system to the user's computing device. Mountingthe file system to the user's computing device may allow a user to viewand browse the files, directories or other data objects in the secondarycopy. However, such mounting often requires the user's computing deviceto also retrieve all of the files or other data objects in the secondarycopy. Retrieving all of the files in the secondary copy may be timeconsuming, since the amount of data being stored is continuing toincrease, and inefficient, since the user may only be looking for a fewfiles, such as files that match a particular search criteria.

Accordingly, aspects of the disclosure provide a system that may reducethe demands placed on system resources and reduce the time consumed by auser when searching for a file. The system may allow a user to providesearch criteria and to mount an abbreviated file system that identifiesfiles, directories or other data objects in a secondary copy that matchthe search criteria. However, unlike typical systems, mounting theabbreviated file system may not involve retrieving all of the files inthe secondary copy. Instead, the abbreviated file system may includejust a listing of files in the secondary copy. Once a user selects,using the abbreviated file system, one or more data objects in thesecondary copy that are of interest, the user's computing device maytransmit a command to have the data objects retrieved (e.g., from anon-production secondary storage media).

Example Data Storage Environment

FIG. 2 is a block diagram illustrating an example arrangement ofresources in a data storage environment. As shown, the data storagesystem 250 may generally include a storage manager 201, a data agent295, a media agent 205, a secondary storage device 215, and, in someembodiments, may include certain other components such as a client 285,a primary data or information store 290, database or index 211, jobsagent 220, an interface module 225, and a management agent 230. Such asystem and elements thereof are exemplary of a modular storage systemsuch as the CommVault Simpana system available from CommVault Systems,Inc. of Oceanport, N.J., and further described in U.S. patentapplication Ser. No. 09/610,738, now U.S. Pat. No. 7,035,880, which isincorporated herein by reference, in its entirety.

A data storage system, such as the system 250, may generally includecombinations of hardware and software components associated withperforming storage operations on electronic data. According to someembodiments of the present disclosure, storage system 250 may be relatedto data storage cells and provide some or all of the functionality ofdata storage cells as described in U.S. patent application Ser. No.09/354,058, now U.S. Pat. No. 7,395,282 which is hereby incorporated byreference in its entirety.

The system of FIG. 2 can be configured to implement a mount view of asecondary copy of a file system or a portion thereof without having toretrieve the actual files or other data objects from secondary storage.For instance, in some cases, an abbreviated mount view is provided basedon user provided search criteria. These techniques will be described infurther detail herein, e.g., with respect to FIGS. 3A-5.

In accordance with certain embodiments of the present disclosure,storage operations performed by storage systems may include creating,storing, retrieving, and migrating primary storage data (e.g., stored onprimary data store 290) and secondary storage data (which may include,for example, snapshot copies, backup copies, HSM copies, archive copies,and other types of copies of electronic data) stored on storage devices215. In some embodiments, storage systems may also provide one or moreintegrated management consoles for users or system processes tointerface with in order to perform certain storage operations onelectronic data as further described herein. Such integrated managementconsoles may be displayed at a central control facility or severalsimilar consoles distributed throughout multiple network locations toprovide global or geographically specific network data storageinformation.

In some embodiments, storage operations may be performed according tovarious storage preferences, for example as expressed by a userpreference or storage policy. A storage policy is generally a datastructure or other information source that includes a set of preferencesand other storage criteria associated with performing a storageoperation. The preferences and storage criteria may include, but are notlimited to, a storage location, relationships between system components,network pathway to utilize, retention policies, data characteristics,compression or encryption requirements, preferred system components toutilize in a storage operation, other criteria relating to a storageoperation, combinations of the same and the like. Thus, in certainembodiments, a storage policy may indicate that certain data is to bestored in a specific storage device, retained for a specified period oftime before being aged to another tier of secondary storage, copied tosecondary storage using a specified number of streams. A storage policymay be stored in the storage manager database 211, to archive media asmetadata for use in restore operations or other storage operations, orto other locations or components of the system.

In certain embodiments, a schedule policy may specify when to performstorage operations and how often and may also specify performing certainstorage operations on sub-clients of data and how to treat thosesub-clients. A sub-client may represent static or dynamic associationsof portions of data of a volume and are typically mutually exclusive.Thus, in certain embodiments, a portion of data may be given a label andthe association is stored as a static entity in an index, database orother storage location used by the system. Sub-clients may also be usedas an effective administrative scheme of organizing data according todata type, department within the enterprise, storage preferences,combinations of the same or the like.

For example, an administrator may find it preferable to separate e-maildata from financial data using two different sub-clients havingdifferent storage preferences, retention criteria, or the like. Storagesystems may contain not only physical devices, but also may representlogical concepts, organizations, and hierarchies. For example, a firststorage system 250 may be configured to perform a first type of storageoperations such as HSM operations, which may include backup or othertypes of data migration, and may include a variety of physicalcomponents including the storage manager 201 (or management agent 230),the media agent 205, the client component 285, and other components asdescribed herein. A second storage system, or cell may contain the sameor similar physical components, however, it may be configured to performa second type of storage operations such as SRM operations, and mayinclude as monitoring a primary data copy or performing other known SRMoperations.

Thus, as can be seen from the above, although the first and secondstorage cells are logically distinct entities configured to performdifferent management functions (i.e., HSM and SRM respectively), eachcell may contain the same or similar physical devices. Alternatively, inother embodiments, different storage cells may contain some of the samephysical devices and not others. For example, a storage systemconfigured to perform SRM tasks may contain the media agent 205, client285, or other network device connected to a primary storage volume,while a storage cell configured to perform HSM tasks may instead includea media agent 205, client 285, or other network device connected to asecondary storage volume and not contain the elements or componentsassociated with and including the primary storage volume. These twocells, however, may each include a different storage manager thatcoordinates storage operations via the same media agents 205 and storagedevices 215. This “overlapping” configuration allows storage resourcesto be accessed by more than one storage manager 201 such that multiplepaths exist to each storage device 215 facilitating failover, loadbalancing and promoting robust data access via alternative routes.

Alternatively, in some embodiments, the same storage manager 201 maycontrol two or more cells (whether or not each storage cell has its owndedicated storage manager). Moreover, in certain embodiments, the extentor type of overlap may be user-defined (e.g., through a control console)or may be automatically configured to optimize data storage and/orretrieval.

Data agent 295 may be a software module or part of a software modulethat is generally responsible for copying, archiving, migrating, andrecovering data from client computer 285 stored in a primary data orinformation store 290 or other memory location. Each client computer 285may have at least one data agent 295 and the system can support multipleclient computers 285. In some embodiments, data agents 295 may bedistributed between client 285 and storage manager 201 (and any otherintermediate components) or may be deployed from a remote location orits functions approximated by a remote process that performs some or allof the functions of data agent 295.

Embodiments of the present disclosure may employ multiple data agents295 each of which may backup, migrate, and recover data associated witha different application. For example, different individual data agents295 may be designed to handle Microsoft Exchange data, Lotus Notes data,Microsoft Windows file system data, Microsoft Active Directory Objectsdata, and other types of data. Other embodiments may employ one or moregeneric data agents 295 that can handle and process multiple data typesrather than using the specialized data agents described above.

If a client computer 285 has two or more types of data, one data agent295 may be required for each data type to copy, archive, migrate, andrestore the client computer 285 data. For example, to backup, migrate,and restore all of the data on a Microsoft Exchange server, the clientcomputer 285 may use one Microsoft Exchange Mailbox data agent 295 tobackup the Exchange mailboxes, one Microsoft Exchange Database dataagent 295 to backup the Exchange databases, one Microsoft ExchangePublic Folder data agent 295 to backup the Exchange Public Folders, andone Microsoft Windows File System data agent 295 to backup the clientcomputers 285 file system. In such embodiments, these data agents 295may be treated as four separate data agents 295 by the system eventhough they reside on the same client computer 285.

Alternatively, other embodiments may use one or more generic data agents295, each of which may be capable of handling two or more data types.For example, one generic data agent 295 may be used to back up, migrateand restore Microsoft Exchange 2000 Mailbox data and Microsoft Exchange2000 Database data while another generic data agent may handle MicrosoftExchange 2000 Public Folder data and Microsoft Windows 2000 File Systemdata, or the like.

Data agents 295 may be responsible for arranging or packing data to becopied or migrated into a certain format such as an archive file.Nonetheless, it will be understood this represents only one example andany suitable packing or containerization technique or transfermethodology may be used if desired. Such an archive file may include alist of files or data objects copied in metadata, the file and dataobjects themselves. Moreover, any data moved by the data agents may betracked within the system by updating indexes associated appropriatestorage managers or media agents.

Generally speaking, storage manager 201 may be a software module orother application that coordinates and controls storage operationsperformed by storage system 250. Storage manager 201 may communicatewith some or all elements of storage system 250 including clientcomputers 285, data agents 295, media agents 205, and storage devices215, to initiate and manage system backups, migrations, and datarecovery.

Storage manager 201 may include a jobs agent 220 that monitors thestatus of some or all storage operations previously performed, currentlybeing performed, or scheduled to be performed by storage operation cell250. Jobs agent 220 may be communicatively coupled with an interfaceagent 225 (typically a software module or application). Interface agent225 may include information processing and display software, such as agraphical user interface (“GUI”), an application program interface(“API”), or other interactive interface through which users and systemprocesses can retrieve information about the status of storageoperations. Through interface 225, users may optionally issueinstructions to various storage systems 250 regarding performance of thestorage operations as described and contemplated by the presentdisclosure. For example, a user may modify a schedule concerning thenumber of pending snapshot copies or other types of copies scheduled asneeded to suit particular needs or requirements. As another example, auser may employ the GUI to view the status of pending storage operationsin some or all of the storage cells in a given network or to monitor thestatus of certain components in a particular storage cell (e.g., theamount of storage capacity left in a particular storage device).

Storage manager 201 may also include a management agent 230 that istypically implemented as a software module or application program. Ingeneral, management agent 230 provides an interface that allows variousmanagement components 201 in other storage operation cells 250 tocommunicate with one another. For example, assume a certain networkconfiguration includes multiple cells 250 adjacent to one another orotherwise logically related in a WAN or LAN configuration (not shown).With this arrangement, each cell 250 may be connected to the otherthrough each respective interface agent 225. This allows each cell 250to send and receive certain pertinent information from other cells 250including status information, routing information, information regardingcapacity and utilization, or the like. These communication paths mayalso be used to convey information and instructions regarding storageoperations.

For example, a management agent in a first storage cell may communicatewith a management agent in a second storage cell regarding the status ofstorage operations in the second storage cell. Another illustrativeexample includes the case where a management agent in first storage cellcommunicates with a management agent 230 in a second storage cell tocontrol the storage manager 201 (and other components) of the secondstorage cell via the management agent 230 contained in the storagemanager 201.

Another illustrative example is the case where management agent 230 inthe first storage cell 250 communicates directly with and controls thecomponents in the second storage cell 250 and bypasses the storagemanager 201 in the second storage cell. If desired, storage cells 250can also be organized hierarchically such that hierarchically superiorcells control or pass information to hierarchically subordinate cells orvice versa.

Storage manager 201 may also maintain an index, a database, or otherdata structure 211. The data stored in database 211 may be used toindicate logical associations between components of the system, userpreferences, management tasks, media containerization and data storageinformation or other useful data, as described in greater detail inapplication Ser. No. 10/818,749, now U.S. Pat. No. 7,246,207, hereinincorporated by reference in its entirety. For example, the storagemanager 201 may use data from database 211 to track logical associationsbetween media agent 205 and storage devices 215 (or movement of data ascontainerized from primary to secondary storage). In addition to theindex 211, the storage system 250 can also include one or more indexesas part of the media agent 205.

The storage manager may control additional information managementoperations including ILM, deduplication, content indexing, dataclassification, data mining or searching, e-discovery management,collaborative searching, encryption, and compression.

Generally speaking, a media agent, which may also be referred to as orbe implemented on a secondary storage computing device 207, may beimplemented as software module that conveys data, as directed by storagemanager 201, between a client computer 285 and one or more secondarystorage devices 215 such as a tape library, a magnetic media storagedevice, an optical media storage device, solid state media, or any othersuitable storage device. In one embodiment, secondary storage computingdevice 207 may be communicatively coupled with and control a secondarystorage device 215. A secondary storage computing device 207 may beconsidered to be associated with a particular secondary storage device215 if that secondary storage computing device 207 is capable of routingand storing data to particular secondary storage device 215.

In operation, a secondary storage computing device 207 associated with aparticular secondary storage device 215 may instruct the storage deviceto use a robotic arm or other retrieval means to load or eject a certainstorage media, and to subsequently archive, migrate, or restore data toor from that media. Secondary storage computing device 207 maycommunicate with a secondary storage device 215 via a suitablecommunications path such as a SCSI or fiber channel communications link.In some embodiments, the secondary storage device 215 may becommunicatively coupled to a data agent 295 via a storage area network(“SAN”). As shown, in certain embodiments, each client 285 cancommunicate with any of the secondary storage computing devices 207,e.g., as directed by the storage manager 201. Moreover, each secondarystorage computing device 207 can communicate with any of the secondarystorage devices 215, e.g., as directed by the storage manager 201. Thus,storage operations can be routed to the secondary storage devices 215 ina dynamic and flexible manner. This inter-networked configurationprovides both scalability and efficient component utilization. Furthercompatible examples of dynamic storage operations are provided inapplication Ser. No. 10/818,749, now U.S. Pat. No. 7,246,207.

Each secondary storage computing device 207 may maintain an index 226, adatabase, or other data structure 226 which may store index datagenerated during backup, migration, and restore and other storageoperations as described herein. For example, performing storageoperations on Microsoft Exchange data may generate index data. Suchindex data provides a secondary storage computing device 207 or otherexternal device with a fast and efficient mechanism for locating datastored or backed up. Thus, in some embodiments, a secondary storagecomputing device index 226, or a storage manager index 211, may storedata associating a client 285 with a particular secondary storagecomputing device 207 or storage device 215, for example, as specified ina storage policy, while a database or other data structure in secondarystorage computing device 207 may indicate where specifically the client285 data is stored in secondary storage device 215, what specific fileswere stored, and other information associated with storage of client 285data. In some embodiments, such index data may be stored along with thedata backed up in a secondary storage device 215, with an additionalcopy of the index data written to index cache in a secondary storagedevice 215. Thus the data is readily available for use in storageoperations and other activities without having to be first retrievedfrom the secondary storage device 215.

Generally speaking, information stored in cache is typically recentinformation that reflects certain particulars about operations that haverecently occurred. After a certain period of time, this information issent to secondary storage and tracked. This information may need to beretrieved and uploaded back into a cache or other memory in a secondarycomputing device before data can be retrieved from secondary storagedevice 215. In some embodiments, the cached information may includeinformation regarding format or containerization of archive or otherfiles stored on secondary storage device 215.

To perform its functions, the media agent 205 may include a media filesystem module 210, a content indexing module 206, and a media agentdatabase 208. While not shown, the media agent 205 can further include adata classification module, a deduplication module, an encryptionmodule, a compression module, a network module, and a distributionmodule.

The media file system module 210 is responsible for reading, writing,archiving, copying, migrating, restoring, accessing, moving,sparsifying, deleting, sanitizing, destroying, or otherwise performingfile system operations on various secondary storage devices of disparatetypes. The media file system module 210 may also instruct the secondarystorage device 215 to use a robotic arm or other retrieval means to loador eject certain storage media such as a tape. The media file systemmodule 210 may also generate an abbreviated file system that can bemounted on a client computer 285, as described below with respect toFIGS. 3A-5.

The media agent(s) 205 can further include a content indexing module 206configured to analyze the contents of primary or secondary copies ofdata objects and/or their associated metadata and to catalogue theresults of this analysis, along with the storage locations of (orreferences to) the primary or secondary copies. This information can bestored in a content index stored within a database 208 associated withthe media agent 205. The content index 206 can be stored in a storagedevice associated with the secondary storage computing device 207 onwhich the particular media agent resides, for instance. The results mayalso be stored elsewhere in the system, e.g., in the storage manager201, along with a secondary copy of the data objects, and/or in an indexcache. Such content index data provides the media agent 205 or anotherdevice with an efficient mechanism for locating primary copies and/orsecondary copies of data objects that match particular criteria. Theindex data or other analyses of data objects or metadata may also beused by a data classification module (not shown) to associate dataobjects with classification identifiers (such as classification tags) inthe media agent database (or other indices) to facilitate informationmanagement policies and searches of stored data objects.

The network module permits the media agent to communicate with othercomponents within the system and hosted services via one or moreproprietary and/or non-proprietary network protocols or APIs (includingcloud service provider APIs, virtual machine management APIs, and hostedservice provider APIs). The deduplication module performs deduplicationof data objects and/or data blocks to reduce data redundancy in thecell. The deduplication module may generate and store data structures tomanage deduplicated data objects, such as deduplication tables, in themedia agent database 208. The encryption module performs encryption ofdata objects, data blocks, or secondary copies of objects to ensure datasecurity in the cell. The compression module 585 performs compression ofdata objects, data blocks, or secondary copies of objects to reduce thedata capacity needed in the cell.

The distribution module may be a set of instructions that coordinatesthe distribution of data objects and indices of data objects. Thedistribution may occur from one client computer 285 to another clientcomputer 285 and/or from hosted services to client computers 285. As afirst example, the distribution module may collect and manage data andmetadata from hosted services or mobile devices. As another example, thedistribution module may synchronize data objects or other objects thatare modified on one client computer 285 so that the same modifiedobjects are available on another client computer 285. As yet anotherexample, the distribution module may distribute indices of data objectsthat originated from multiple client computers 285 and/or hostedservices, so a user can access all of their data objects through aunified user interface or a native application on their client computer285. The distribution module may also initiate “live browse” sessions topermit communications between different client computers 285 so that thedevices 285 can interchange data and metadata or so the devices 285 canprovide computing resources, such as applications, to each other.

In some embodiments, certain components may reside and execute on thesame computer. For example, in some embodiments, a client computer 285,such as a data agent 295 or a storage manager 201, coordinates anddirects local archiving, migration, and retrieval application functionsas further described in U.S. patent application Ser. No. 09/610,738.This client computer 285 can function independently or together withother similar client computers 285.

Furthermore, components of the storage system of FIG. 2 can alsocommunicate with each other via a computer network. For example, thenetwork may comprise a public network such as the Internet, virtualprivate network (VPN), token ring or TCP/IP based network, wide areanetwork (WAN), local area network (LAN), an intranet network,point-to-point link, a wireless network, cellular network, wireless datatransmission system, two-way cable system, interactive kiosk network,satellite network, broadband network, baseband network, combinations ofthe same or the like.

Additionally, the various components of FIG. 2 may be configured fordeduplication. For example, one or more of the clients 285 can include adeduplicated database. The data stored in the secondary storage devices215 or primary data stores 290 may also be deduplicated. For example,one or more of the media agents 205 associated with the respectivesecondary storage devices 215 can manage the deuplication of data in thesecondary storage devices 215.

The storage system 250 can perform various types of storage operations,such as, for example, replication, snapshots, archiving and the like. Adescription of some storage operations compatible with embodimentsdescribed herein is provided near the end of this disclosure.

Search-Based Mount

As described above, the media agent(s) 205 may be configured to conveydata between the client computer(s) 285 and one or more secondarystorage devices 215. In some circumstances, a user of one of the clientcomputers 285 may wish to search through data stored in the secondarystorage devices 215 to identify and retrieve a particular data object orgroup of data objects (e.g., one or more files). The media agent 205 maybe configured to deliver an abbreviated file system that can be mountedon the client computer 285. For instance, in some embodiments theabbreviated file system identifies secondary copies of data objects thatmeet the user's search criteria. The user may be able to browse theabbreviated file system and select any secondary copies of data objectsthat are of interest, and the media agent 205 may retrieve just theselected the data objects from secondary storage.

FIG. 3A depicts an illustrative user interface 300 that enables a userto search secondary copies such as backups, archives, and/or snapshotsstored in the secondary storage device(s) 215. As illustrated, the userinterface 300 includes various drop-down menus 302 and commands 304. Oneskilled in the art will appreciate that the drop-down menus 302 and thecommands 304 can be organized, grouped, and displayed in a variety ofdifferent ways. The user interface 300 may be produced or hosted, forexample, by the storage manager 201, and specifically the interfaceagent 225, described above with respect to FIG. 2.

Within the user interface 300, a user may be able enter search criteria.For instance, the user can enter a search term in box 310. In someembodiments, the user may also be able to refine the search. Forexample, in box 312 the user may be able to identify which backup,archive, or snapshot that the search should be performed in. Forillustrative purposes only, backup 316A is selected as the backup thatthe search should be performed in. In addition, the user may be able toenter additional search criteria via the options button 314. Additionalsearch criteria may include choosing to search for one or more filetypes within the file system that was backed up, archived, or a snapshotwas taken of, choosing to search only specific folders in the filesystem, choosing to search for data objects that were generated,accessed, or modified during a certain time period, and the like.

In an embodiment, once the user has entered a search term and/orselected any additional search criteria, the search term(s) and/or otherfiltering criteria may be transmitted by the storage manager 201 to theappropriate media agent 205. As described above, the content indexingmodule 206 of a media agent 205 may generate a content index of asecondary copy (e.g., a backup, archive, or snapshot) and store itwithin the media agent database 208. The media agent 205, and inparticular the content indexing module 206, may use the content index tolocate secondary copies of data objects that match the search termand/or other search criteria.

In some embodiments, the media agent 205 may identify the data objectsin the secondary copy that match the search term and/or criteria, butmay not retrieve these copies from one or more of the secondary storagedevices 215. Instead, for example, the media agent 205, via the mediafile system module 210, e.g., may generate an abbreviated file systemthat provides links or pointers to the copies of the data objects in thesecondary copy that match the search term(s) and/or other filteringcriteria. The links or pointers, however, may not point directly to thelocation where the copies of data objects in the secondary copy arestored. Rather, selection of the links or pointers may generate commandsinstructing the media agent 205 to retrieve the copy of the data objectin the secondary copy.

The abbreviated file system may be structured as a file system tree,listing folders and data objects as they are structured in the filesystem that has been copied to secondary storage (e.g., backed up,archived, or had a snapshot taken). In an embodiment, the structure ofthe actual file system may be included in the content index and may beused to generate the abbreviated file system.

In some embodiments, just those folders and/or data objects thatcorrespond to the copies of data objects in the secondary copy thatmatch the search term(s) and/or other filtering criteria may be listedin the abbreviated file system. In other embodiments, all folders anddata objects in the file system are listed in the abbreviated filesystem; however, folders or data objects that do not correspond to thecopies of data objects in the secondary copy that match the searchterm(s) and/or other filtering criteria may be shaded or otherwiseidentified as not matching the search term(s) and/or other filteringcriteria.

The client computer 285 may receive the abbreviated file system from themedia agent 205. As described above, the client computer 285 may receivethe abbreviated file system, but not the actual copies of the dataobjects from secondary storage that the abbreviated file systemidentifies. In an embodiment, the client computer 285 may mount theabbreviated file system. For example, the operating system of the clientcomputer 285 may mount the abbreviated file system to make it accessiblevia the file system of the client computer 285. The abbreviated filesystem may appear as a new drive or partition within the file system ofthe client computer 285 (e.g., as the “E:\” drive).

FIG. 3B depicts an illustrative user interface 350 that enables a userto browse through the abbreviated file system. As illustrated, the userinterface 350 includes various drop-down menus 352 and commands 354. Oneskilled in the art will appreciate that the drop-down menus 352 and thecommands 354 can be organized, grouped, and displayed in a variety ofdifferent ways. The user interface 350 may be generated by the operatingsystem of the client computer 285. In an embodiment, the user interface350 represents the view produced by the operating system when a userattempts to browse through the file system of the client computer 285.

In an embodiment, the icon 356A represents the file system of the clientcomputer 285 (e.g., the “C:\” drive), which may also be referred to as aprimary copy or “live” version of the file system. The icon 356Brepresents an optical drive coupled to the client computer 285 (e.g.,the “D:\” drive), and the icon 356C represents the mounted abbreviatedfile system (e.g., the “E:\” drive) representing a portion of thesecondary copy of the file system. If, for example, a back up, archive,or snapshot had been taken of the C:\ drive at a previous time, the E:\drive may represent the back up, archive, or snapshot.

Like with the C:\ drive and the D:\ drive, a user may browse the E:\drive by expanding and contracting folders, such as folder 318A.However, as described above, the media agent 205 may not immediatelyretrieve the copies of data objects in the secondary copy that match thesearch term(s) and/or other filtering criteria. Accordingly, unlike theC:\ drive and the D:\ drive, which may provide a listing of folders andfiles and direct access to the files since they are stored locally, theE:\ drive merely provides a listing of folders and files. The copies ofdata objects in the secondary copy that correspond to the listed filesare not stored locally in memory associated with the client computer285. Instead, the copies of the data objects in the secondary copyremain in the one or more secondary storage devices 215. As describedbelow, the listing of files in the abbreviated file system may includelinks or pointers, which may allow a user to retrieve a selected filefrom one or more of the secondary storage devices 215.

As illustrated in FIG. 3B, the abbreviated file system includes threefolders, folder 318A, folder 318B, and folder 318C, and an emailexchange folder 336. In an embodiment, folder 318A may be expanded asindicated by the “+” in the box to the left of the folder 318A icon.However, folder 318B may not be expanded as indicated by the fact thatthe box to the left of the folder 318B icon is shaded. Because folder318A may be expanded, this may indicate that it includes a listing of afile that corresponds to a copy of a data object in the secondary copythat matches the search term(s) and/or other filtering criteria. Becausefolder 318B may not be expanded, this may indicate that it does notinclude a listing of any file that corresponds to a copy of a dataobject in the secondary copy that matches the search term(s) and/orother filtering criteria. While FIG. 3B illustrates folder 318B as beingshaded, folder 318B may be marked in any way (e.g., a special icon, adifferent font, highlighting, etc.) to indicate that it does not includea list of a file that corresponds to a copy of a data object in thesecondary copy that matches the search term(s) and/or other filteringcriteria.

As illustrated in FIG. 3B, folder 318C is expanded, and includes a listof secondary copies of data objects that match the search term(s) and/orother filtering criteria. While FIG. 3B depicts folder 318C as includinga document 320′, a spreadsheet 325′, a presentation 330′, a music orvideo file 332′, and an image file 334′, the folder 318C may include ornot include any type of file or data object. In addition, the folder318C may only display those secondary copies of the data objects thatcorrespond to the search term(s) and/or other filtering criteria. Theactual file system from which the abbreviated file system was generatedmay include additional data objects in folder 318C that do notcorrespond to the search term(s) and/or other filtering criteria.

As illustrated in FIG. 3B, the email exchange folder 336 is alsoexpanded, and includes a list of mailboxes 338A-B that each includesecondary copies of data objects that match the search term(s) and/orother filtering criteria. Specifically, each mailbox 338A and 338Bincludes one or more electronic messages, such as electronic message345′, that match the search term(s) and/or other filtering criteria.

In an embodiment, a user may select any one or more of the data objects(e.g., by hovering over the listing, by clicking the listing, bydouble-clicking the listing, by a gesture, by voice commands, etc.) inorder to retrieve the data objects from secondary storage. For example,if the user selects the image file 334′, the client computer 285 maysend a transmission to the media agent 205 indicating that the imagefile 334′ has been selected. The media agent 205, for example via themedia file system module 210, may retrieve the image file 334′ from oneor more of the secondary storage devices 215, and transmit the imagefile 334′ to the client computer 285.

Abbreviated File System Building Process

FIG. 4 shows a flow diagram illustrative of embodiments of a routine 400implemented by a media agent 205 for generating an abbreviated filesystem. The elements outlined for routine 400 may be implemented by oneor more computing devices/components that are associated with the mediaagent 205. For example, routine 400 can be implemented by any one, or acombination of the network module, the content indexing module 206, themedia file system module 210, and the like. Accordingly, routine 400 hasbeen logically associated as being generally performed by the mediaagent 205, and thus the following illustrative embodiment should notconstrued as limiting.

At block 402, the routine 400 receives a search term and/or otherfiltering criteria, as previously discussed with respect to FIGS. 3A-B.In an embodiment, the search term may also include search criteria tofurther refine the search. In a further embodiment, the routine 400 mayalso receive information relating to which secondary copy (e.g., backup, archive, or snapshot) the search should be performed in. The searchterm and/or any additional filtering criteria may be received from aclient computer 285 via the storage manager 201 (e.g., via the interfaceagent 225).

At block 404, the routine 400 identifies data objects in the secondarycopy that match the search term or other filtering criteria. In anembodiment, the routine 400 may identify the data objects in thesecondary copy by searching through a content index of the back up,archive, or snapshot that is to be searched and using the receivedsearch term or other filtering criteria. However, the routine 400 mayonly identify, and not retrieve, the data objects in secondary storage.

At block 406, the routine 400 generates an abbreviated file system basedon the data objects in the secondary copy that match the search term. Inan embodiment, the abbreviated file system comprises metadatarepresenting a file tree and is structured similarly to or the same asthe actual file system. The abbreviated file system may indicate whichdata objects in the secondary copy match the search term (and may onlyinclude a listing of those data objects that match the search term).

At block 408, the routine 400 transmits the abbreviated file system tothe client computer 285. In an embodiment, an operating system of theclient computer 285 may mount the abbreviated file system so that itappears and can be navigated via the file system of the client computer285. As described above, the routine 400 may only transmit theabbreviated file system, not the actual data objects, to the clientcomputer 285.

Abbreviated File System Mounting and Data Retrieval Process

FIG. 5 shows a flow diagram illustrative of embodiments of a routine 500implemented by a client computer 285 for mounting an abbreviated filesystem and retrieving a copy of a data object from secondary storage.The elements outlined for routine 500 may be implemented by one or moreclient computers/components that are associated with the client computer285. For example, routine 500 can be implemented by any one, or acombination of the operating system of the client computer 285, anapplication running on the client computer 285, data agent 295, and thelike. Accordingly, routine 500 has been logically associated as beinggenerally performed by the client computer 285, and thus the followingillustrative embodiment should not construed as limiting.

At block 502, the routine 500 transmits a search term to a media agent205. In an embodiment, the search term may also include other criteriato further refine the filtering of the secondary copy data. In a furtherembodiment, the routine 500 may also transmit information relating towhich secondary copy (e.g., back up, archive, or snapshot) the searchshould be performed in. The search term and any additional informationmay be transmitted via the storage manager 201 (e.g., via the interfaceagent 225).

At block 504, the routine 500 receives an abbreviated file system fromthe media agent 205, where the abbreviated file system was generated bythe media agent based on the search and any additional information. Inan embodiment, the abbreviated file system is represented as a file treeand structured similarly to the actual file system that was backed up,was archived, or a snapshot was taken of. The abbreviated file systemmay indicate which data objects in the secondary copy match the searchterm (and may only include a listing of those data objects that matchthe search term) or otherwise satisfy the filtering criteria. Asdescribed previously, the routine 500 may not receive the actual dataobjects at this point.

At block 506, the routine 500 mounts the abbreviated file system. In anembodiment, mounting the abbreviated file system means that it appearsand can be navigated via the file system of the client computer 285,e.g., using a GUI such as the user interface 350 of FIG. 3B.

At block 508, the routine 500 identifies a data object selected by auser in the mounted abbreviated file system. In an embodiment, theabbreviated file system may include a list of folders and files, andlinks or pointers may be provided for those data objects that correspondto copies of the data objects in secondary storage that match the searchterm. In order to retrieve the data object, a user may select a dataobject in the abbreviated file system, via the user interface 350 or acommand line, for example. The link or pointer may include a commandinstructing the media agent 205 to retrieve the selected data object.Once a file is selected, the routine 500 may send the command orinstruction to the media agent 205.

At block 510, the routine 500 receives the data object that wasselected. In an embodiment, the copy of the data object is received fromone or more secondary storage devices 215 via the media agent 205 whenthe user requests the copy.

In some aspects, the abbreviated file system allows a user to search forand receive results identifying which data objects in the secondary copymatch the user's search term(s) and/or other filtering criteria. Becausethe actual copies of the data objects are not transmitted to the userfrom secondary storage until the user specifically requests retrieval ofthe data objects (e.g., the data objects themselves are not transmittedto the user's device when the abbreviated file system is mounted), thesearch process may be less data-intensive, preserving resources andproviding faster results. In addition, mounting the abbreviated filesystem may be more convenient for the user, as the user may search forand find the desired data by browsing through the file system of theuser's computing device rather than via a separate application.

In further embodiments, an unabbreviated file system may be mounted inthe same manner as the abbreviated file system described above. Forexample, before a search is performed, the media agent 205 may send anunabbreviated file system to the client computer 285 to be mounted. Theunabbreviated file system may include just a listing of folders andfiles in the file system, but may include all folders and files in thefile system (e.g., not just those folders and files that correspond to adata object in the secondary copy that matches a search term(s) and/orother criteria). A user may be able to view the unabbreviated filesystem in a user interface, such as the user interface 350, and retrieveany selected data objects in the secondary copy in the same manner asdescribed above with respect to the abbreviated file system.

Further Embodiments and Explanation of Terminology

Storage operations compatible with embodiments described herein will nowbe described. For example, data can be stored in primary storage as aprimary copy or in secondary storage as various types of secondarycopies including, as a backup copy, a snapshot copy, a hierarchicalstorage management copy (“HSM”), an archive copy, and other types ofcopies.

A primary copy of data according to some embodiments is a productioncopy or other “live” version of the data which is used by a softwareapplication and is generally in the native format of that application.Such primary copy data is typically intended for short term retention(e.g., several hours or days) before some or all of the data is storedas one or more secondary copies, such as, for example, to prevent lossof data in the event a problem occurred with the data stored in primarystorage.

Secondary copies can include point-in-time data and are typicallyintended for long-term retention (e.g., weeks, months or years) beforesome or all of the data is moved to other storage or is discarded.Secondary copies may be indexed so users can browse and restore the dataat another point in time. After certain primary copy data is backed up,a pointer or other location indicia such as a stub may be placed in theprimary copy to indicate the current location of that data.

One type of secondary copy is a backup copy. A backup copy in someembodiments is a copy of production data and, in some embodiments, canbe stored in a backup format, e.g., as opposed to a native applicationformat. For example, a backup copy may be stored in a backup format thatfacilitates compression and/or efficient long-term storage. Backupcopies generally have relatively long retention periods and may bestored on media with slower retrieval times than other types ofsecondary copies and media. In some cases, backup copies may be storedat on offsite location.

Another form of secondary copy is a snapshot copy. From an end-userviewpoint, in some embodiments, a snapshot may be thought of as aninstant image of the primary copy data at a given point in time. Asnapshot generally captures the directory structure of a primary copyvolume at a particular moment in time and may also preserve fileattributes and contents. In some embodiments, a snapshot may exist as avirtual file system, parallel to the actual file system. Users typicallygain read-only access to the record of files and directories of thesnapshot. By electing to restore primary copy data from a snapshot takenat a given point in time, users may also return the current file systemto the state of the file system that existed when the snapshot wastaken.

A snapshot in some cases is created substantially instantly, using aminimum amount of file space, but may still function as a conventionalfile system backup. Some types of snapshots do not actually createanother physical copy of all the data, but may simply create pointersthat are able to map files and directories to specific disk blocks.

In some embodiments, once a snapshot has been taken, subsequent changesto the file system typically do not overwrite the blocks in use at thetime of the snapshot. Therefore, the initial snapshot may use only asmall amount of disk space needed to record a mapping or other datastructure representing or otherwise tracking the blocks that correspondto the current state of the file system. Additional disk space isusually required only when files and directories are actually modifiedlater. Furthermore, when files are modified, typically only the pointerswhich map to blocks are copied, not the blocks themselves. In someembodiments, for example in the case of copy-on-write snapshots, when ablock changes in primary storage, the block is copied to secondarystorage before the block is overwritten in primary storage. The snapshotmapping of file system data is also updated to reflect the changedblock(s) at that particular point in time.

An HSM copy can be a copy of the primary copy data but typicallyincludes only a subset of the primary copy data that meets a certaincriteria and is usually stored in a format other than the nativeapplication format. For example, an HSM copy may include data from theprimary copy that is larger than a given size threshold or older than agiven age threshold and that is stored in a backup format. Often, HSMdata is removed from the primary copy, and a stub is stored in theprimary copy to indicate the new location of the HSM data. When a userrequests access to the HSM data that has been removed or migrated,systems use the stub to locate the data and often make recovery of thedata appear transparent, even though the HSM data may be stored at alocation different from the remaining primary copy data.

An archive copy according to some embodiments is generally similar to anHSM copy. However, the data satisfying criteria for removal from theprimary copy is generally completely removed with no stub left in theprimary copy to indicate the new location (i.e., where the archive copydata has been moved to). Archive copies of data are sometimes stored ina backup format or other non-native application format. In addition,archive copies are generally retained for very long periods of time(e.g., years) and, in some cases, are never deleted. In certainembodiments, such archive copies may be made and kept for extendedperiods in order to meet compliance regulations or for other permanentstorage applications.

In some embodiments, application data over its lifetime moves from moreexpensive quick access storage to less expensive slower access storage.This process of moving data through these various tiers of storage issometimes referred to as information lifecycle management (“ILM”). Thisis the process by which data is “aged” from forms of primary storagewith faster access/restore times down through less expensive secondarystorage with slower access/restore times. For example, such aging mayoccur as data becomes less important or mission critical over time.

Similar data transfers associated with location-specific criteria areperformed when restoring data from secondary storage to primary storage.For example, to restore data a user or system process generally mustspecify a particular secondary storage device, piece of media, orarchive file. Thus, the precision with which conventional storagemanagement systems perform storage operations on electronic data isgenerally limited by the ability to define or specify storage operationsbased on data location.

Terminology

Conditional language, such as, among others, “can,” “could,” “might,” or“may,” unless specifically stated otherwise, or otherwise understoodwithin the context as used, is generally intended to convey that certainembodiments include, while other embodiments do not include, certainfeatures, elements and/or steps. Thus, such conditional language is notgenerally intended to imply that features, elements and/or steps are inany way required for one or more embodiments or that one or moreembodiments necessarily include logic for deciding, with or without userinput or prompting, whether these features, elements and/or steps areincluded or are to be performed in any particular embodiment.

Depending on the embodiment, certain acts, events, or functions of anyof the algorithms described herein can be performed in a differentsequence, can be added, merged, or left out all together (e.g., not alldescribed acts or events are necessary for the practice of thealgorithms). Moreover, in certain embodiments, acts or events can beperformed concurrently, e.g., through multi-threaded processing,interrupt processing, or multiple processors or processor cores or onother parallel architectures, rather than sequentially.

Systems and modules described herein may comprise software, firmware,hardware, or any combination(s) of software, firmware, or hardwaresuitable for the purposes described herein. Software and other modulesmay reside on servers, workstations, personal computers, computerizedtablets, PDAs, and other devices suitable for the purposes describedherein. Software and other modules may be accessible via local memory,via a network, via a browser, or via other means suitable for thepurposes described herein. Data structures described herein may comprisecomputer files, variables, programming arrays, programming structures,or any electronic information storage schemes or methods, or anycombinations thereof, suitable for the purposes described herein. Userinterface elements described herein may comprise elements from graphicaluser interfaces, command line interfaces, and other suitable interfaces.

Further, the processing of the various components of the illustratedsystems can be distributed across multiple machines, networks, and othercomputing resources. In addition, two or more components of a system canbe combined into fewer components. Various components of the illustratedsystems can be implemented in one or more virtual machines, rather thanin dedicated computer hardware systems. Likewise, the data repositoriesshown can represent physical and/or logical data storage, including, forexample, storage area networks or other distributed storage systems.Moreover, in some embodiments the connections between the componentsshown represent possible paths of data flow, rather than actualconnections between hardware. While some examples of possibleconnections are shown, any of the subset of the components shown cancommunicate with any other subset of components in variousimplementations.

Embodiments are also described above with reference to flow chartillustrations and/or block diagrams of methods, apparatus (systems) andcomputer program products. Each block of the flow chart illustrationsand/or block diagrams, and combinations of blocks in the flow chartillustrations and/or block diagrams, may be implemented by computerprogram instructions. Such instructions may be provided to a processorof a general purpose computer, special purpose computer, or otherprogrammable data processing apparatus to produce a machine, such thatthe instructions, which execute via the processor of the computer orother programmable data processing apparatus, create means forimplementing the acts specified in the flow chart and/or block diagramblock or blocks.

These computer program instructions may also be stored in acomputer-readable memory that can direct a computer or otherprogrammable data processing apparatus to operate in a particularmanner, such that the instructions stored in the computer-readablememory produce an article of manufacture including instruction meanswhich implement the acts specified in the flow chart and/or blockdiagram block or blocks. The computer program instructions may also beloaded onto a computer or other programmable data processing apparatusto cause a series of operations to be performed on the computer or otherprogrammable apparatus to produce a computer implemented process suchthat the instructions which execute on the computer or otherprogrammable apparatus provide steps for implementing the acts specifiedin the flow chart and/or block diagram block or blocks.

While certain embodiments have been described, these embodiments havebeen presented by way of example only, and are not intended to limit thescope of the disclosure. Indeed, the novel methods and systems describedherein may be embodied in a variety of other forms; furthermore, variousomissions, substitutions and changes in the form of the describedmethods and systems may be made without departing from the spirit of thedisclosure. The accompanying claims and their equivalents are intendedto cover such forms or modifications as would fall within the scope andspirit of the disclosure.

What is claimed is:
 1. A system comprising: a computing deviceconfigured to: transmit filtering criteria to a secondary storagesubsystem, the secondary storage subsystem including one or moresecondary storage devices that store a secondary copy of at least aportion of a file system; receive, from the secondary storage subsystem,metadata corresponding to a version of the secondary copy, wherein theversion of the secondary copy comprises an identification of one or morefiles and directories in the secondary copy that satisfy the filteringcriteria; show the version of the secondary copy in a file structurelayout; receive an indication of a selection of an identification of afirst file or directory in the secondary copy; transmit, to thesecondary storage subsystem, a request for a copy of the first file ordirectory; and receive the copy of the first file or directory from thesecondary storage subsystem.
 2. The system of claim 1, wherein thecomputing device is further configured to receive the copy of theselected first file or directory from the secondary storage subsystemvia one of a local area network or a wide area network.
 3. The system ofclaim 1, wherein the filtering criteria comprises a search termcomprising text and an identification of the secondary copy, thesecondary copy comprising at least one of a back up copy, an archivecopy, or a snapshot copy in which a search should be performed toidentify files or directories which include one or more instances of thetext in metadata associated with the files or directories, in contentassociated with the files or directories, or both.
 4. The system ofclaim 3, wherein the version of the secondary copy comprises anidentification of one or more files and directories including one ormore instances of the text and an identification of one or more filesand directories not including one or more instances of the text, andwherein the identification of each file and directory including one ormore instances of the text is identified differently than theidentification of each file and directory not including one or moreinstances of the text.
 5. The system of claim 1, wherein a filestructure of the version of the secondary copy is the same as a filestructure of the secondary copy.
 6. The system of claim 5, wherein thefiles and directories in the secondary copy comprise second files anddirectories that correspond to unidentified files and directories thatdo not match the filtering criteria and third files and directories thatcorrespond to the identified files and directories that do match thefiltering criteria.
 7. The system of claim 6, wherein the version of thesecondary copy comprises an identification of the identified files anddirectories, and wherein the listing does not include the unidentifiedfiles and directories.
 8. The system of claim 1, wherein the version ofthe secondary copy is displayed within a graphical user interface in thefile structure layout such that the one or more files and directoriesappear to be stored by the computing device in memory.
 9. A method forsearching a file system, the method comprising: transmitting, by acomputing device, filtering criteria to a secondary storage subsystem,the secondary storage subsystem including one or more secondary storagedevices that store a secondary copy of at least a portion of a filesystem; receiving, from the secondary storage subsystem, metadatacorresponding to a version of the secondary copy, wherein the version ofthe secondary copy comprises an identification of one or more of filesand directories in the secondary copy that satisfy the filteringcriteria; showing the version of the secondary copy in a file structurelayout; receiving an indication of a selection of an identification of afirst file or directory in the secondary copy; transmitting, to thesecondary storage subsystem, a request for a copy of the first file ordirectory; and receiving the copy of the first file or directory fromthe secondary storage subsystem.
 10. The method of claim 9, whereinreceiving the copy of the first file or directory comprises receivingthe copy of the first file or directory from the secondary storagesubsystem via one of a local area network or a wide area network. 11.The method of claim 9, wherein the filtering criteria comprises a searchterm comprising text and an identification of the secondary copy, thesecondary copy comprising at least one of a back up copy, an archivecopy, or a snapshot copy in which a search should be performed toidentify files or directories which include one or more instances of thetext in metadata associated with the files or directories, in contentassociated with the files or directories, or both.
 12. The method ofclaim 11, wherein the version of the secondary copy comprises anidentification of one or more of the files and directories in thesecondary copy including one or more instances of the text and anidentification of one or more of the files and directories in thesecondary copy not including one or more instances of the text, andwherein the identification of each file and directory including one ormore instances of the text is identified differently than theidentification of each file and directory not including one or moreinstances of the text.
 13. The method of claim 9, wherein the version ofthe secondary copy is displayed within a graphical user interface in thefile structure layout such that the one or more files and directoriesappear to be stored by the computing device in memory. 14.Non-transitory physical computer storage comprising executableinstructions stored thereon that, when executed in a processor, areconfigured to implement operations for searching a file system, theoperations comprising: transmitting filtering criteria to a secondarystorage subsystem, the secondary storage subsystem including one or moresecondary storage devices that store a secondary copy of at least aportion of a file system; receiving, from the secondary storagesubsystem, metadata corresponding to a version of the secondary copy,wherein the version of the secondary copy comprises an identification ofone or more files and directories in the secondary copy that satisfy thefiltering criteria; showing the version of the secondary copy in a filestructure layout; receiving an indication of a selection of anidentification of a first file or directory in the secondary copy;transmitting, to the secondary storage subsystem, a request for a copyof the first file or directory; and receiving the copy of the first fileor directory from the secondary storage subsystem.
 15. Thenon-transitory physical computer storage of claim 14, wherein theoperations further comprise receiving the copy of the selected firstfile or directory from the secondary storage subsystem via one of alocal area network or a wide area network.
 16. The non-transitoryphysical computer storage of claim 14, wherein the filtering criteriacomprises a search term comprising text and an identification of thesecondary copy, the secondary copy comprising at least one of a back upcopy, an archive copy, or a snapshot copy in which a search should beperformed to identify files or directories which include one or moreinstances of the text in metadata associated with the files ordirectories, in content associated with the files or directories, orboth.
 17. The non-transitory physical computer storage of claim 16,wherein the version of the secondary copy comprises an identification ofone or more files and directories including one or more instances of thetext and an identification of one or more files and directories notincluding one or more instances of the text, and wherein theidentification of each file and directory including one or moreinstances of the text is identified differently than the identificationof each file and directory not including one or more instances of thetext.
 18. The non-transitory physical computer storage of claim 14,wherein a file structure of the version of the secondary copy is thesame as a file structure of the secondary copy.
 19. The non-transitoryphysical computer storage of claim 18, wherein the files and directoriesin the secondary copy comprise second files and directories thatcorrespond to unidentified files and directories that do not match thefiltering criteria and third files and directories that correspond tothe identified files and directories that do match the filteringcriteria.
 20. The non-transitory physical computer storage of claim 19,wherein the version of the secondary copy comprises an identification ofthe identified files and directories, and wherein the listing does notinclude the unidentified files and directories.